If you have V4 running and go to open V3, V4 pops back up. It doesn’t matter which version you start first, if you go to open the other version, the running version pops back up.
Hello John. Thank you for reporting it. Fixed!
Does it mens that now we can use V3 and V4 together, on one pc can work V3 and on other V4, and separated server can run one database. Database can be used by V3 and V4?
No. The v3 and v4 databases are not compatible with eachother. They each require their own DB.