Ah - yes. Another LDDP quirck. It does auto rounding, something BAD on intermediate files. On really tiny quads, rounding can warp things enough to go above recommended warp (1°) or even above maximum warp (3°). For more background on coplanarity, see LDraw specification, and documentation of Planarcheck.
This is not a big issue, since it's easy to correct by splitting the warped quad (a triangle is always planar
Planarcheck and Datheader can do it for you automatically. I'd recommend Planarcheck here, because Datheader always inserts a condline between the triangles after the split, something not useful here (the surfaces are supposed to be planar!). Planarcheck also defaults to add condline, but there is an option to prevent that. Maybe the mysterious condline you see was added during a Datheader check?
Now let's come back to LDDP. In Tools > Options > Configurations values tab, there is a check box that prevent LDDP to do automatic rounding. I strongly suggest you to do that... Unfortunately, there is also a bug: when you do a color change, rounding occurs regardless of the checkbox!!! Because of this I mostly do color changes using MLCad... You may also increase the number of digits of "position decimal accuracy" to 5 digits.
Only in the last step, try to reduce precision to 3 digits (the recommended value for parts), and run Planarcheck to clear coplanarity errors.
BTW, looks like the parameters tweak in slicerpro was successful? I see no more gaps!
This is not a big issue, since it's easy to correct by splitting the warped quad (a triangle is always planar
Planarcheck and Datheader can do it for you automatically. I'd recommend Planarcheck here, because Datheader always inserts a condline between the triangles after the split, something not useful here (the surfaces are supposed to be planar!). Planarcheck also defaults to add condline, but there is an option to prevent that. Maybe the mysterious condline you see was added during a Datheader check?
Now let's come back to LDDP. In Tools > Options > Configurations values tab, there is a check box that prevent LDDP to do automatic rounding. I strongly suggest you to do that... Unfortunately, there is also a bug: when you do a color change, rounding occurs regardless of the checkbox!!! Because of this I mostly do color changes using MLCad... You may also increase the number of digits of "position decimal accuracy" to 5 digits.
Only in the last step, try to reduce precision to 3 digits (the recommended value for parts), and run Planarcheck to clear coplanarity errors.
BTW, looks like the parameters tweak in slicerpro was successful? I see no more gaps!