5 minutes first run in new folder, or any next run ?
Maybe some database files created outside of "release" or "debug" folder. After you copy folder content to another location, SQLite must create new database (Or maybe your database useabsolute patch for files)
1. Try run executable and inspect his activity (CPU, Memory, Disk usage) by "Resources Inspector" on Windows - for "bottleneck" detecting.
2. Make Virtual Mashine with clean Windows, and test your installer on VM.