There are various suggestions in the forum for resolution, texture and loading problems. I have not heard of not being able to potions again after the required delay, and never had to move more than a couple steps the few times an object was blocking the summoning of my creature.
When I test play a game I try the demo. Lack of a demo means the developer doesn't want me to buy the game, unless I get a good recommendation from a trusted source and the price drops enough to make it an acceptable gamble.
