PROBLEM SOLVED, that was it the pot slider was too closed from the end even it was not touching it...so the travel when pushed was not long enough to trigger the launcher which was pobably worse in my case because I used a log type pot. I moved the pot of about 1cm and it works fine.
Would like to thank you mjr YOU ARE THE MAN !!!! really appreciated the way you worked on this case,,,no blabla perfect troubleshooting tracking method...straight!!!...these few posts will help a lot of people in the same case hopefully.
Thx KiwiBri also to have followed this discution without interfering in the discussion for nothing like it could be with some people on some technical forums...givethx for acting as professionnals both of you for the good of everybody.....BIIIIIIG UP