well, welsh is not perfect
his books are great. trainspotting is the best thing i've ever read and ecstasy was also smart and funny but to make a movie with these stories... hum, bad idea. yeah, i watched the film with this voice in my head saying THIS IS NOT TRAINSPOTTING 2 but a second voice came to remind me each second how bad it was.
Is not funny, smart, well written and directed. a big mess, a *beep* nowhere. welsh tried to be surrealism but failed. with nick hornby, chuck pahlaniuk and bret ellis, he's one of the best writer of his generation. but let the adaptation of your books to professional screenwriter...
like we said in french, in my town... on est dans une vrai belle merde