After running Dmsconv, then logging into datasource for the first time, it prompts me to create tables. I click yes, but get a message “Spatial version record mismatch” and it fails to update\create spatial tables.
After running Dmsconv, then logging into datasource for the first time, it prompts me to create tables. I click yes, but get a message “Spatial tables creation Failed” and it fails to update\create spatial tables.
Followed by Last Error  Cannot Login to the Datasource. Database Version Mismatch. One or more custom tables need conversion. The ProjectWise DMSCONV conversion application and the ProjectWise Administrator must be used before logging into the Datasource.
The issue is not the DMSCONV process, it is more related to the mounting of a datasource to a new ProjectWise environment and it not having access to the ProjectWise storage area that holds the dmsSystem folder to create the necessary files and tables for Spatial.
If you are in a test environment, Create a test storage area.
Before running DMSconv, log into ProjectWise explorer and determine which storage area holds the dmsSystem folders. Click on the dmsSystem folder and view the folder properties.
Log into ProjectWise administrator and change the storage area for this storage to your test storage area in your test environment.
Now Run the Dmsconv.
When completed and if successful, log into the ProjectWise administrator, create the Datasource and log in.
You will be prompted to create Spatial tables. Check the box to convert tables, then click Convert
When installing the ProjectWise Administrator, there is a feature that can be turned on or off call the "Spatial Administrator". If this feature is installed; When launching ProjectWise Administrator and logging into a datasource, the Spatial feature checks the datasource schema for the tables needed for the Spatial feature. If not found, then it will prompt you to install these tables or if the tables are found it may fail with Last Error 
Why would the tables be found if we are not using the Spatial feature?
If you are not using the Spatial features, then there is no need to install the Spatial administrator.
The ProjectWise Implementation guide under "Upgrade and Planning", step 3.