Grimrock

I really like(d) this game, and I've put in 17 hours of gameplay, and I finally got one of my characters at full Armour points, so she could wear the heavy armour because she's the only front character that needs it -- my minotaur sure doesn't. So, I spend hours collecting all this awesome heavy armour and my minotaur nicely carries it around, until my Shadow character finally gets full Armour capability. I dress her up all fancy in it, and find she can't even move, it's so heavy. Well what was the goddamn point of that? I expected having Heavy Armour Proficiency would allow me to be proficient at wearing heavy armour. Apparently not. It took SO LONG to gain all those attribute points, and the game won't even let me respec her, unless I want to script it, and even then I can only add points, which is cheating. So now she's decked out in about 15 hours worth of useless attribute points.
I'm so irritated at the whole stupid affair I just stopped playing altogether. At least let players reassign attribute points to make up for these sorts of situations, or maybe, make the heavy armour actually wearable by more than just the giant raging beast who needs it less than any of them, by reducing its weight significantly/increasing carrying capacity significantly, once proficiency has been reached.

...I'm going to go read a book. >.<

The overlooked trait of endurance would be nice for that character. A bit late now, but for when you try again...
Reduce food consumption by 25% is almost irrelevant, but 25KG more carrying capacity is very handy.
What class and race is she?
There are 3 main types of heavy armour, each a different weight.
It might be worth checking if the lightest set works.
She only needs amour and a weapon or two. Make your Minotaur carry everything else.

The Armor skills does two things:
a) it grants a general increase in Protection for each skill point placed into the skill
b) it removes the penalty of decreased Evasion for wearing Light and/or Heavy Armor

Now what the Armor skill does NOT grant is the Strength required to keep moving after gearing up. After all heavy armor is .. well .. heavy. It's a no-brainer that a heavy armor user needs to build up his/her Strength enough so s/he is at least able to wear all equipped gear without being overburdened.

Right now all you can do is as FennerMachine suggests: swap any non-equipped stuff in your heavy armor users inventory to other characters. When s/he still can't move after doing this you need to build up his/her Strength. This can be done in several ways, even after game start:
- equip gear that adds Strength, like the Brace of Fortitude
- drink Potions of Strength, either found or self-made
- get Athletics skill level 3 for an additional 15 kg of carrying capacity

Also...

Heavy armor is heavy, but it isn't all equally heavy. Some sets and pieces are relatively light-weight.

You don't have to equip all heavy armor at once. Swap in a piece at a time until you can build up carrying capacity. In the meantime, you'll still get the extra 10% to the Protection value of light pieces.

There are also various items that increase the wearer's strength or carrying capacity.

also you might want to give some potions of perma-strength. That raises carrying capacity.