In TA the race-style numbering system was changed and many of the cosmetic pieces were remodeled to improve symmetry, fix hardpoints that did not quite point in the right direction, etc.
While this is a good thing for ships designed within TA, it means that a lot of models from DA or DL can't be directly copied over without either completely overhauling them or replacing the old models back into TA (which while it'd fix the ones you're copying in, it'd mangle the new templates similarly). So the actual solution would be to do both--copy the old models back over with different names, so they're accessible but don't replace the new ones, then update your ship design files in notepad to use them. But it's a lot of work, so only you can decide if it's really worth it.
@Kryo, it is possible to bring a DA ship to ToA ship. How do you update your ships desin files in the notepad. What is it you actually do?
@Spearthrower, 267 ships in template file, does that make you problems with "Our of Memory" error? It has happen to me alot even if I set it on 10,000MB
Saint Mina of Ophelia VII of Order of the Bloody Rose of Orders Militant of Adepta Sororitas
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“We are at war with forces too terrible to comprehend. We cannot afford mercy for any of its victims too weak to take the correct course. Mercy destroys us; it weakens us and saps our resolve. Put aside all such thought. They are not worthy of Inquisitors in the service of Our Emperor GmOOnii. Praise his name for in our resolve we only reflect his purpose of will.”
Inquisitor Draco,
Castigations on the Last Days
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