I have some legacy ACAD drawings with about 250 viewports (3 per detail, many details).  I can activate/toggle visibility/Ctrl+R for about 48 of the viewports, but that's all.  I can see some of the others and even list their properties, but I can not activate them or see the geometry at all (its not hidden, and toggling visibility makes no difference).  I can't even print these because I just get the drawing borders - no geometry.  If I Ctrl+drag one, it does make a copy with the same offset/zoom/etc, but all layers are visible.

Is there a limitation to the number of viewports DraftSight can render?  Or can it not properly process these legacy files?  Or maybe I'm just missing something (I am a noob with DS).

The file does open fine in ACAD and these viewports can be activated without any issues at all.

Thanks in advance!