I agree with all the posts and this is a very serious issue. I've tried various local "peat free" composts from a variety of nurseries and garden centres and none of them have performed well. I experienced nearly all of the above problems; seedlings not growing, roots rotting, nasty green slime etc. forming after 2-3 days of sowing seeds/potting up, one batch of compost dried to the consistency of a concrete brick after just 2 days! And it had been well watered!!!
If you're growing fruit and vegetables this is also a health issue - although by the sounds of it no one has had much luck getting their plants to the stage where they can actually harvest the crops.
I reckon this needs to be investigated much further, and it'll take more than tipped out compost on the floors of the DIY sheds, although that's a good start!
Here's an article from the States, and I have this feeling that something similar is going on over here with our compost:
Hello Gardener's World, anybody listening to our cries for help here?
One very frustrated gardener.
I've just read your link, and I think it's interesting, although it covers the problems associated with clopyramid (sp) which has been a problem over here, but more associated with horse manure than with compost per se. I think the problem that horses were eating grass that had been treated, and, since it (the chemical) was not broken down by the horses' digestion, it remained active for some 12 months+. The problems with compost are more to do with the reduction of peat content and the inclusion of poorly-composted rubbish which is causing so many problems.