Need LDPC help

[Jaco van der Molen]

1. Yes, though often it's not worth the trouble. Use primitives only if you can use matching primitives/negative primitives otherwise you'll have troubles with primitive substitution where primitives and soup of triangles meet. Here you should use a 1-4ring1 primitive for the lower right black ring (and you could possibly use a 3-4disc primitive instead of 3 x 1-4disc).
2. Unfortunately no, which makes this a mess to do. I'd probably use LDPE for that since it doesn't have this kind of restriction (LDPE also allows to make multiple translations/duplications at once which is very powerful here!
3. No you can't. once you select a primitive, all other selections are forgotten.
4. We are supposed to be able to do so (file -> import from dat -> append as subpart) but it doesn't seem to work exactly as I would expect (rotated subparts)... perhaps someone else has more experience with this?

Ah yes there is a 3-4disc too!