I have been experiencing the same issue. No luck so far in getting it to work.
I already tested 1.6.0 and our trainer still works even today on 3/9/2016..
it appears the trainer is up to date with 1.6.0. All code areas match with the current trainer. Problems with construction, what units are you using or faction? There is also Encampment construction option.. did you use it? Are you using the trainer as described?
best,
Cal