today I want to share with you my guess regarding why Acumatica can't restore snapshot bigger then 2 Gb. As far as I see at database level, all files are going into table UploadFileRevision. If to look into structure of this table, you'll find that it has column data, which looks like this:
if to google a bit, you'll find that maximum size which Varbinary(MAX) can accomodate is 2 Gb.
That's why if you snapshot is bigger then 2 Gb, look for other way of restoring of your snapshot
As of now it is my guess on why snapshot can't be restored. I'll update everybody how to deal with this, once I'll find solution, which satisfies me completely.