Hi, so you just captured the portals, but not a connection between rooms? Then it could be possible, that it won’t be merged into one component, as there won’t be common parts… As I asked before, are there in the project ground control points with coordinates in some coordinate system? If so, it could be merge as georeferenced components. If not, you will need to capture another connection images.
Also I noticed, that your capturing style is not ideal, as it seems, that you were standing on one place and captured images from it and then you moved to another position (like pivot capturing):
This is not ideal for photogrammetry, as you can see on this comparison:
This long processing time can be related with the way how you captured your images. There is a short tutorial how to capture images for RealityCapture: https://www.youtube.com/watch?v=9e_NLp_FaUk&t=4s
In which step do you have these crashes? During model creation or alignment?
Yes, there could be a memory outage. For this it could achieve 1 TB of data (for all your models). Are you processing this on more computers?
I think we don’t have power and source to process such big project.