I wonder might it have been Rand's very lack of AoL training that stopped any of the forsaken trying to mess with any of his wards. If he had access to LTT at that time his channeling would have followed rules all the male forsaken would have been familiar with. LTT learned his craft under the same system they did so they would know how he would go about setting wards and how to deal with them.

Rand on the other hand was a lot like Nynaeve who was doing things by instinct. we have seen enough of Nynaeve's channeling compared to other Aes Sedai to know that she did sometimes achieves the same effect as an AS but by using completly differnent weaves. In TGS she even comments on her self taught abilities and being able to do things no other AS could but on the other hand finding it very hard to unlearn bad habits she picked up on her own.

When he first set the wards around Callandor Rand was a wild tallent. His weavings might make no sense to a classically trained AoL channeler. Added to that he was using one of the most powerful Sa'angreal ever made to give his weaving strength.

When you have super powerful weaves and possibly woven in a way that makes no sense to a forsaken the prize might suddenly not be worth the risk given that you might not be able to predict what the ward will do if you get it wrong. A pillar of balefire descending on you could really ruin one's day.

As for the Egwene not raiding the store room I put that down to political reasons. Even if they are not attacking AS directly (and they don't know that for certain, what if a sister is in the room at the time) its an armed action where she is trying to get the conflict resolved without fighting. Yes the Younglings were raiding the soldiers of the rebel army but sisters had not attacked other sisters. Egwene herself had a pov where she was afraid that if it came to sisters fighting sisters things could get out of hand and you have AS blood in the halls which would make real unification more difficult