Root Problem rooting my Desire HD

Hey guys

Finally took the plunge and tried rooting using the sticky thread.

Main reason is just to uninstall some apps that seems to have come bundled with my (largely unbranded) Three UK handset, such as Amazon mp3 and Midomi.

Anyway, I installed Visionary+ r14 and tried a temp root.

All that happens is the handset slows to a crawl, and the app page for visionary goes blank, even if I open something else then try to come back to it.

Also, system app installer says the handset isn't rooted.

Can anyone shed any light on this?

Many thanks in advance