Using 4.4.1, I can create a new portal using one of the pre-defined portal templates (Personal, Club or Organisation etc), but when I try and create one using a template created via the "Export Portal Template" function, the app just hangs. I have left it running for 20 minutes and it just sits there. Nothing in error log. Entry appears in Portals table, but nothing in PortalAlias (even tho I have entered a valid alias).
I have tried with and without content.
The process appears to timeout after the same number of pages every time. The portal template contains 53 tabs, but when I view the portal list containing newly created portal (without alias and unable to access settings function), my new portal only contains 25 tabs.
Browsing to new portal, I get a page cannot be displayed.
The file is valid xml and appears on basic inspection to read ok.

Would be much appreciated if someone could shed some light on this.