Hm, I'm not sure what you mean; tried loading up with all of the Amator mods, and just Coal & Steam by itself, alongside mini machines, and the technologies appeared just fine.
The only issue I noticed is that when playing with all Amator mods, was the mini storage tank not properly requiring the new prereq tech that unlocks the base storage tank, but despite that, all mini machines were still researchable, as far as I could tell.
There might be another mod in your modlist that is affecting this issue?
EDIT: Uploaded a new version with some possibly related fixes, by forcing Amator's mods to load first, that might resolve any missing tech issues.
