Installation fails: EditCtls.ocx registration

[Slaughterteddy]

Dear All,

Has any one seen this problem? The installation fails with:

"C:\Windows\system32\EditCtlsU.ocx
Unable to register the DLL/OCX: RegSvr32 failed with exit code 0x3.
Click Retry to try again. Ignore to proceed anyway (not recommended)
or Abort to cancel installation."

Dependency Walker comes up with several errors:
"Error: At least one required implicit or forwarded dependency was not found.
Error: At least one module has an unresolved import due to a missing export function in an implicitly dependent module.
Error: Modules with different CPU types were found."

Before looking at the second two, the first one is generated because it cannot find QT5CORE.DLL, QT5GUI.DLL and QT5NETWOTK.DLL. Sure enough, they aren't anywhere under windows. Am I meant to install the QT 5 system?

Note that I uninstalled Bullzip, and then did a complete Windows repair install. No change in behaviour.

ATB

Slaughter