First, you can still export registry settings with regedit in old Win9x/NT4 format as pure MS-DOS text files. Use the "Save as type" field before save. I don't really know the reason why Microsoft changed the format, but I guess, it is because of Asian characters in paths which need two bytes.

Registry files in new format are coded in UTF-16 with BOM (Byte Order Marker) with MS-DOS line endings (CR+LF).

To edit registry files in new format, set following options in UltraEdit at the general configuration dialog.

Automatically convert to DOS format - (On)
Auto detect UTF-8 files - (On)
Write UTF-8 BOM header to ALL UTF-8 files when saved - (Off)
Write UTF-8 BOM on new files created within this program (if above is not set) - (On)
Detect Unicode(UTF-16) files without BOM - (On)
Save file as input format (UNIX/MAC/DOS) - (On)

With this settings, you should not have problems to edit most type of files.

The option "Write UTF-8 BOM on new files created within this program" has no influence on new text files as long as you do not convert your new ASCII file with the File - Conversions - ASCII to UTF-8 command to an UTF-8 file. So normal new ASCII files are still saved as pure ASCII files without a BOM.

An advantage of "old" registry format is the smaller file size - only half of the new format. For American and European versions of Windows, there should be no problem using old format. I never had one.

Another advantage of old format is, that the Insert File command of UltraEdit works without a problem. UltraEdit v11.10b still has problems with finding the correct file position and removing the BOM, if inserting a UTF-16 file into an already opened UTF-16 file.