After searching the net for the better part of 2 days and going over every trash link I could find, I FINALLY found a working HOMM2 GUI saved game editor similar to the one I remember using back in the 90's.

Works perfectly (win10) on the GOG gold version, all save types, normal and expansion and both campaigns.
You can use it to edit both your and the NPC's:
1) Hero stats, movement, skills, spells, items.
2) Troop types, positions & quantity.
3) Resources.

Quite simply, this is everything you'll want/need in a saved game editor.

Edited portion below: Cnet changed the file type extension to ".rar.txt" just delete the .txt portion and it's fine. Reason 12,697 why I hate Cnet

I guess you guys can also just google:

burton tsang HOMM2

and go to his cnet page to download. it should be the first search result

ordinarily I loath cnet, but in this one instance they actually do something worthwhile....

Good find. This is more convenient that using hex-editor, however with hex editor you can edit your game "on the fly" so to speak and it might be more fun to use hex-editor anyway :). Also, you can find more stuff to change that is not featured in this editor. For example, change game time - month, week, day, change if player is human or AI controlled, change castle allegiance (flag), castle name, garrison, available creatures to buy from dwellings, spells that castle's mage guild contains, spells per magic guild level, if tows is allowed to be upgraded to castle, buildings in castle... lot's of stuff. :)

Of course, there is matter of finding the stuff you need ;)

You need 5+ rep to post link. GOG did this to prevent spammers.

You can get around this restriction by putting the link in quote tags.

FANTASTIC! Thanks for the info.
I've edited the orig posting with the direct link.
Oh, and if GoG (or anyone else) see's fit, they may want to archive and host this (it's freeware according to publisher) before CNET manages to screw things up as they inevitably do... LOL!

Ah, CNET still automatically starts playing video ads with sound on their pages. Good to see some things don't change; still down to their usual standards.

Thanks for the link.

Alas! I tried downloading it, but I get an error:

This XML file does not appear to have any style information associated with it. The document tree is shown below.
<Error>
<Code>NoSuchKey</Code>
<Message>The specified key does not exist.</Message>
</Error>

Anyone got the download to share?