Changing sites

[Floundering]

Hi,
I recently went onto FullTilt Poker to try it out since I can get rakeback there (and the deposit bonus). When I left Pokerstars I had 24% ROI for tournaments (mainly played single table sit-n-goes).
After playing 20 or so SnG's I have an ROI of -100%. Of course I will stop playing at FTP as soon as I get my next bonus increment (very soon thankfully, otherwise I would just go without it...), but I am curious if anyone else has had something like this happen when they have changed sites? I tried different games from $1-$11 SnG's (single tables) but cannot even place! What am I doing wrong at FT that I wasn't at PS??? Ideas anyone?