AMade my first batch of modelling chocolate last night using milk chocolate and golden syrup I'm in the uk when I took it out this morning it had white lumpy bits in it but most of them went away when moulding to shape is this normal or what have I done wrong ? it tastes better than fondant and I have to say fun to work with

AI can never get it to work with golden syrup, I just buy corn syrup from amazon or big tesco stores sometimes have it, the only other thing g that works for me is liquid glucose but it's way too expensive to use in any quantity :-)

Hope that helps, if you're not happy with yours as is the now try kneed g a little sugar paste in, it might help :-)

Sounds like it might have been the cocoa butter separating a little - it should knead back in again once you start to work with it.  What quantities of chocolate and syrup did you use?  I use equal amounts but I always use plain chocolate, have never tried it with milk chocolate so you might need a bit extra chocolate if using milk.
 

I have not tried making it with golden syrup yet, although it is on my to do list (less processed and better tasting than corn syrup), but from what I have read in tutorials, you can get some lumpy bits if there were little bits of chocolate that were not completely incorporated with the syrup. I haven't had this issue myself.  I tend to overmix and end up oily (letting it rest and kneading it well seems to cure that so far). I have read that people have had success using honey instead of corn syrup and that it gives a nice flavor. I have a hard time finding golden syrup here in the states except in a very small jar, so I will likely try honey next.