Got a big problem here guys, need help if possible, I brought and install Jagged Alliance 2 last night, since then I have not been able to load one single saved game, it makes no difference if I saved in tactical screen or map screen, everytime it would say "error loading game", tried starting different new games to make this is not a single incident, and it is not. I am running Jagged Alliance 2 on a brand new laptop, Window Vista, Intel Centrino Duo 2.00G, with 4GB of RAM. All other game I brought from GOG seem to work fine on this laptop; Fallout 2, Fallout tactics etc.
Please help, any suggestion or advice will be great.

Ok, basic troubleshooting starting then, let's see if we can narrow it down a bit.
First of all, which version of 1.13 did you download? Latest stable should be 4870, available from here. If you have an older version, the following steps should still work, though there may have been a few changes since then.
Assuming you haven't messed with the VFS (and if you have, the you should probably know enough to tell me if you did so), you should be using the 1.13 profile, which has the vfs defined in the file "vfs_config.JA2113.ini".
First two lines in that file should be:
[vfs_config]
PROFILES = SlfLibs, Vanilla, v113, UserProf

And a bit lower you should have
[PROFILE_UserProf]
NAME = Player Profile
LOCATIONS = uprof_root
PROFILE_ROOT = Profiles\UserProfile_JA2113
WRITE = true

In case the above lines do exist, create the folder "Profiles\UserProfile_JA2113" and drop the SavedGames folder there.
In case the first two lines differ, find the last entry of it (in this example it's UserProf), loof for the [PROFILE_UserProf] equivalent, and see what the PROFILE_ROOT folder is. If this doesn't work either, I'd suggest asking for help at The Bear's Pit forum, or at the Bear's Pit IRC.
Be aware that most of us on the IRC are europeans, so do take that in mind for what times to connect at, though I don't think it will be a problem for you.

Whoa.. I'm running version 2085.

Could I patch the game first or is that gonna make the saved games unusable?

And how do you patch it in that case, I'm not too used to doing this kind of stuff.

2085 is ancient in terms of JA2 development (2 years or more as I recall), so installing 4870 will definately break save game compatibility. IMHO though, it is worth it, even if only for the New Attachment System (aka NAS), which allows each weapon to have a multitude of attachment points instead of just 4. You also get a lot more features, though I can't recall them all atm, even though you also get the NCTH which doesn't have the best implementation in that release.
To update, you will need a clean install of JA2 (zip it or copy it somewhere, so you can easily re-install if/when needed) and you should be able to extract the 4870 archive over it.
As to getting your saves to work, check the vfs.config file I mentioned above. Depending on how long you've spent playing though, grabbing the newer version may be advisable.

Got the patch working and I've got to say that it is a stunning ammount of stuff that has been made available trough this mod to my favourite game I have been playing for the past 15 years,

I am a bit clueless as to how some of the stats for my personal merc works though, some are easily understanble while others; not so much.
Is there possibly some chart available as to how these new perks and stuff work?

EDIT: I can't say I'm liking the new targeting reticule, I liked the one where you have the normal reticule and the addition of the small bar that shows how high of a chance you have of hitting in 2085 version.

And also I do think I prefer having the previous numbers for AP cost on actions.

Is there a way to change this?

Anything you want to change can be changed, that's the beauty of 1.13
For the new Aiming Reticule (which is actually a whole new aiming system) go to Options (or is it preferences?), next page, and untick the "Use NCTH". In later versions this has been moved to the new campaign screen, but as I recall 4870 has it at the options menu.
For the AP cost, you can modify the file Data-1.13\APBPConstants.ini and change the AP_MAXIMUM = 100 to AP_MAXIMUM = 25, but in my opinion the 100 based system offers a bit more flexibility, since a pistol that had a draw cost of 1 AP (out of 25) may now have 2-6 AP, so there is a difference between weapons. Your call though, feel free to change it.
Also, one of the most often asked questions is why your IMP uses more APs to walk/run than the other mercs, the answer is that he is wearing a backpack. Backpacks are used to haul stuff around, and unless they have the extra mortar rounds that you will need in the battle, it's best to drop them once you enter battle (there's a button in the merc's inventory for it).

Take an hour or two to look through the JA2_Options.ini, either by using notepad or by using the INI Editor, there is a lot of customizable stuff there, and as usual, should you have any questions, ask away.
Enjoy 1.13

Thank you for all the help Jmich, I've no regrets deleting my old saves now.

Nice to see a player dedicated to such an old gem of a game, don't know what I would've done otherwise.

/salute

Now, time to take out the trash :-)

I see why people complain about the difficulty of the Drassen counterattack..

I just fought off about 50 soldiers with my 5 mercs, sure as hell wasn't easy but I got a lot of stuff now :-P

50? So few?
Yes, the Drassen Counter Attack (DCA) is one of the most brutal (and fun) battles in the game, which you can turn off through the ini file. With a bit of planning and preparation (and ambushing the groups before they attack) you can gear your mercs with quite a lot of excellent weapons. A way to postpone the counterattack is by not liberating all of Drassen, capture the airport (for BR access) and the mine (for income), and leave the middle sector occupied, thus not triggering the DCA. Or just go out there and show them what happens if they try to attack you ;)

Actually all I used was pistols for the mercs, except for my own which had the 50 round 9mm rifle whatever it's called.
All I did was have my 5 mercs bunker themselves inside the bar in the Mine part of Drassen against one of the walls facing to the side of the door; making best use of turn interruptions and the fact that AI seemingly always have such great manners to close the door after they've opened it and come in resulting in no AP.

I seem to have encountered another "issue" though.

Belive that I might have screwed up the summoning of the Crepitus even though I'm on Sci-fi Mode by skipping past the cinematic where the queen tells Elliot to "stop feeding bodies to the creatures"

I find fighting the Crepitus problably the most fun in the entire game, aside from having 3 groups of mercs fending off troops continuously one sector before the queens palace in the end of the game... something tells me this isn't fixable (?) :/

I know the "Meanwhile" messages appeared WAY long ago already, more than 2 months have passed in my game.

Here is my save: http://www.2shared.com/file/lI4l3nJD/SaveGame01.html

As you can see the only thing I haven't explored yet is Meduna and Orta..

Is that the right save?

I'm unsure, folders might have gotten mixed up.

Unsure, haven't had the chance to see it yet. Also, just a quick check, you do have Crepitus enabled in the ini, right?

Yeah, it is enabled.

Just noticed I also cannot recruit Carlos nor Miguel even though the only unexplored bit I've left is the Queens palace :/

Whats different in insane mode?

Is it just the number of opponents or other things aswell? Depending on this I might be willing to start over