I updated to 11.5.2. Valentina Studio Pro.
Had been using 10.6.3.
The project file is in the same folder as the db file.
Opening the project file for the first time in 11.5.2, there wasn't a connection with the db. I choose the db. One form may work, but the connection breaks when using another form. I deleted the datasource and created a new one and that didn't work. Have tried several times without success.