What are the differences in terms of performance between having turning a Sketchup object into an Enscape Proxy vs turning it into an Enscape Custom Asset? This for a Sketchup object which is about 45MB on its own.
Is it correct to assume that the Custom Asset would be better?
There shouldn't be much of a difference performance-wise, but when it comes to usability as well turning it into a Custom Asset is really not the wrong way! 
Especially for a smaller model like that - we probably wouldn't recommend having a whole city for example as an Asset since that may also mean it could go over the allowed polygon count.
"... it could go over the allowed polygon count."
Wondering what the limit might be..?
Wondering what the limit might be..?
Sure! That would be 20k. Everything over 20k and you'll get a warning before creating the Asset. It is actually still possible to create and use the Asset then, but this may result in a crash of Enscape, although it's way more likely that you "only" run into performance issues and visual issues like the object not being visible in off-screen reflections. So in the end it's "allowed", but usually not recommended. Hope that helps!
this would most likely result in a crash of Enscape
Why would cause the crash? Is it inherent to the gltf loading process, or should we expect this for any object even if it's a .skp proxy?
Why would cause the crash? Is it inherent to the gltf loading process, or should we expect this for any object even if it's a .skp proxy?
I have adjusted my previous response - in the end, a crash is actually not likely actually, my apologies for the confusion. What's more likely, as mentioned above now, is that you'll run into performance problems and over-20k-objects may not be displayed in off-screen reflections.
If you have both a powerful machine and a project where there aren't too many reflective surfaces (or the objects don't have to be visible in reflections) then you can still go for it. 20k is still the usual limit we recommend as it's also usually enough for a high-quality model.
Our Assets for example use a lot less than 20k polygons per object and they still look excellent and don't eat up a lot of performance at all.
