Hello,
If you have downloaded and installed from the following URL, the UPDM does not work on the 64-bit version of Enterprise Architect.
https://sparxsystems.com/products/mdg/#updmNow we can use the UPDM profile (and also UAF 1.1) without the add-in when we use the Unified or Ultimate editions because the UPDM profile is now built-in.
But the built-in profile does not have the validation rule, so you cannot use the validation.
I do not know if we can use the UPDM add-in on 32-bit Enterprise Architect because, as I wrote above, Enterprise Architect already has a built-in UPDM profile, so the profiles will be duplicated.
I think the UPDM add-in is useless because the latest add-in was released 10 years ago. We cannot use the validation, but it is better to use the latest built-in UPDM (or UAF 1.1).
HTH,