We have had issues with a ThinApp since testing on Windows 10 1803. I raised a ticket with VMware who have responded that the latest version, 5.2.3, is only supported with Windows 10 1703.
I asked for a timescale on support but there doesn't appear to be one, and the impression I was given was that 1709 would get support first before 1803.
I'm afraid it looks like you will have to downgrade to 1709 or 1703.
this is the answer from VMWare:
As of now Windows 10 1803 is not supported with VMware Thinapp. Our team is working on the same and we don't have an ETA at the moment.
Kindly let us know if you have further queries. Have a nice day ahead!
I'm wondering if I'll have it...