Hi Folks.
A heads-up on a possible bug the final Mecc level "The Battle". When deploying the popup bomb, it just sits there doing nothing for a minute or two, then disappears. I've tried over and over, all over the map, but no luck. This is frustrating, needless to say, since the level can't be finished without it. The bomb has worked in all the other levels before this - only in this level is there a problem. I finally gave up and will replay the level again from scratch to see if the problem remains. I thought it was worth mentioning, however, in case anyone else runs into this.
Some details: This is a fresh install of the GOG version on Windows XP, fully patched with GRM, GiantsHook and the GeForce3 converter. My character died a few times, and since the level is long and any buildings built remain when you restart, I kept playing rather than starting over. Due to a dumb error, I died after the base was fully built and all the intermediate objectives were already met - only the final objective remained.
It's possible that restarting with most of the level complete is what triggers the bug. Hard to say until I play through again. Since I've worked out the strategy now, I should be able to play through in one pass. Hopefully this does the job, because as fun as the level is, it's pretty long.

Yeah, I might try that too. Like I said, I want to give it a go first without dying and triggering the "keep your buildings on restart" feature, since I suspect that might be involved. If that doesn't work, removing the mods is the next step.
Heh. Since I've experienced firsthand the era when this game was new (and long before), I'm used to workarounds. That's just how it was back in the day. :-)

I played through the level again. I can definitely verify a glitch. For those of you playing through for the first time, heads up.
I managed to get through most of the level until my character died. When the level was restarted and I finished building the gift shop, it acted funny. When I walked up to the door, I actually went inside the model instead of triggering the gift shop menu. By walking back and forth at the front door, I could trigger the desired response, but it was very localised and tricky to find. Once inside, I took one of the mini-turrets. When deployed, it would not work, just like the popup bomb before. When deployed the turret would not quite sit on the ground properly but would float a bit in the air. After a few minutes it would disappear. Same behavior elsewhere on the map. Everything else worked.
When I got to the stage with the popup bomb, I grabbed one immediately, went to a remote spot and tried it. Boom - it worked. Great!
So I played on until the endgame was in sight. Fetched a popup bomb, deployed it at the designated place and ... nothing. Just like before.
Next attempt will be without mods installed. I used up my discretionary time with my last 2 attempts at the level, so I won't be able to take a stab at it until later in the week. We'll see whether a pristine GOG install works better. Hopefully the savegames don't contain the bug.
Note: This isn't a call for help - I'm able to work through this stuff just fine. This particular level is so long, it just takes time to change things and try again. I'm reporting this so it's known in case someone else runs into this and so the GOG folks are aware, since there isn't a bug/issue tracker yet.

Hi guys, Giants is notorious for its scripting bugs and other assorted glitches. I remember this happening back when it was originally released and ended up using the unlock all levels cheat to play the next stage.
After playing the gog.com version recently the same thing happended on one of Delphi's base building levels. I unleased the tornado spell on the barracks or whatever it is, it blew up and then nothing happened. I went all the way back through the level to kill any remaining patrols trying to trigger the end of the stage and nothing changed.
Thankfully, I think the game is fun enough to perservere through these things, possibly play the stage again and hope everything works properly. Otherwise you may just have to skip that level using the cheat, which isn't ideal.

Just a followup.
I've tried this level a few more times, taking care not to die in the middle. So far no luck. I've experienced random failures of items (like the little machine gun turrets) - each time through it's different. There is definitely something funny going on. Very frustrating, since the Battle level is quite long. I certainly would have finished the game by now if it were not for this (and purchased more GOG games as a result).
brasop says Giants is notorious for scripting bugs and other glitches. Based on my experience, I would agree. Uninstalling all the mods etc. and trying the level again with only the raw game code is my next step. Hopefully I will find my way through this level eventually so I can continue the game. It's too good to give up now.
Over the long term, I think the value-add for GOG will have to expand to include necessary bug fixes, not just lack of DRM and tweaks to ensure playability on XP/Vista. That's quite a tall order and may be too much to ask, particularly if the source code is not available. Since this is a commercial venture, however, I hope that if the revenue stream is sufficient enough resources could be devoted to setting up a bug tracking system and taking a shot at fixing a few things. I think I would even pay a bit more for patching an already purchased GOG game to eliminate any show-stopper bugs. After all, it's DRM free, so valuable enhancements that customers subsidize will be rewarded by increased long-term value with respect to replayability.