Ignition and blinker problems

Let me start from the beginning in case anything is related. about 42K Had to replace tranny. they never replaced the nuetral safety switch at that time and never bothered to tell me that that's why the back up lights came on when it was in neutral. Finally found that our and replaced it after having to also buy the pig-tail wire to replace on the wiring harnes for the tranny since the sealant GM used originally turned to glue and would not allow the switch to be unplugged. Along that same time It became common for the Key to stick in the ignition...won't turn all the way off as if car is still in gear. That stopped for a while after replacing the switch but now its happening again. What might the problem be here? is there something messed up with teh switch on the steering column or is it that nuetral/safety switch again???? Also the other day we were driving along in cruise control and put the blinkers on to pass someone and the cruise control shut off...after that we noticed that when the blinkers were on and you put the breaks on the blinkers stopped blinking....what might that be caused by? They did start working normally a couple of days later. I just can't understand all the wierd stuff that happens....