Hello
Converter installation consists of 3 services and 2 drivers (excluding the client that does not register in SCM). Most probably you have a problem with one of the drivers. Those are the bitmap driver (SCM name bmdrvr) and vstor driver (vstor2-mntapi20-shared). Take in to account that the bitmap driver cannot be stopped once started (i.e. machine restart is needed). It starts when the machine is being used as a source of incremental conversion. If this is the case, check whether the conversion job has been finalized; otherwise the bitmap driver starts on each machine start to keep tracking the disk changes.
The 3 services are the agent (vmware-converter-a.exe, service name vmware-converter-agent), worker(vmware-converter-w.exe, service name vmware-converter-worker), and server (vmware-converter.exe, service name vmware-converter-server). These are user space processes that can be killed.
There is nothing much interesting in registry apart from registration of these services, but if you want, see "HKCU\Software\VMware, Inc.\VMware vCenter Converter Standalone" and "HKLM\Software\VMware, Inc.\VMware vCenter Converter Standalone". The files are in "%ProgramFiles(x86)%\VMware\VMware vCenter Converter Standalone" and "%ALLUSERSPROFILE%\VMware\VMware vCenter Converter Standalone" (+ client stuff in %LOCALAPPDATA%\VMware vCenter Converter Standalone Client")
HTH
Plamen