Very difficult if you don't know what to search for
I don't know anything about anything Mac OS, but if this happened to me I would reinstall the offending program and uninstall it thoroughly with an specialist uninstaller program, of which there are many for Windows and I presume for Macs too.
Otherwise, do a Mac version of 'system restore' to a date/time before Videoglide was installed, then reinstall Debut.
I hope you get it sorted.