Not sure why Usals isn't working for you. I have a twinhan 1020, using the bda driver for xp(although I'm using Vista, it seems to work fine).
Import one of the Joshyfun ini files. Set up your diseqc info, don't forget to click "do now" then "ok". Down below set lof1 and lof2 from the drop down boxes, click apply at the bottom. In the right hand pane, click "sel all", then "scan". The dish should move to that bird and scan, it may take a while to move. Most of the time I have to re-scan because Mytheatre is scanning while the dish is still moving to the bird and I miss some channels.
Maybe you have another problem, your dish should move when you select either v or h transponders, you say it will only work on h, do you have a switch in line? If so, try withou it, might be a cable problem?