Problems shifting in the tranny..

I had a thread not to long ago about my rebuilt transmission. Still looking for options...Car is in great shape, the tranny isn't completely shot but it has has a hard time switching gears. If i play with the accelerator i can get it to shift....but obviously I don't drive it on a regular basis at this point..it's been parked for about a year...i have the money to fix it now...what should I do?? rebuild again?? is this a problem anyone has heard of?? Should i rebuild the existing one and immediatley get a tranny cooler?? A little confused.