Hello Wolfgang,
To send a diagnostic file you need to attach it to a support ticket here:
https://www.hauptwerk.com/submit-ticket/
(I think you need to be logged into your account on MDA's website in order to be able to do that.)
As an aside, ASIO drivers are much better than DirectSound -- they give lower latencies and usually allow higher polyphony, and better resilience to audio glitches, and potentially allow multi-channel output where applicable. If you have a dedicated professional/semi-professional audio interface then it would normally have a manufacturer-supplied ASIO driver, so it's best to select that on the "General settings | Audio device" screen in Hauptwerk. If you don't currently have a dedicated audio interface (e.g. if you're just using the PC's built-in sound output) then you may find that the freeware ASIO4All driver works with it.
See also the "Performance tuning | Audio interface and drivers" section in the main Hauptwerk user guide (page 293 in the current v7.0 version) for that, and also the "Performance tuning | Other operating system and computer optimizations and diagnostics" section (pages 308-310) regarding troubleshooting audio/driver problems. For example, it's usually important to make sure that no other software (including Windows itself) is trying to play audio through the relevant audio interface at the same time that Hauptwerk's using it. Also, if it's a USB audio interface then make sure that the Windows power-saving options for putting USB devices to sleep are disabled (see half way down page 308), and that you don't try to plug in, or unplug, and audio, MIDI, or USB devices whilst Hauptwerk is running.