Zen crashing Reaper

[IIRs]

Hi,

Trying Zen for the first time in Reaper 3.74 / Vista laptop / ASIO4ALL + headphones for now.

I'm getting regular crashes while switching presets. So far its happened when switching from Rhino presets to other Rhino presets, and also (the last time) while attempting to switch from a Rhino preset to a Twin2 preset. This is the crash report copied below: notice the fault is apparently in Rhino rather than Twin2.

(Is there a proper procedure for reporting bugs?)

Problem signature:
Problem Event Name: APPCRASH
Application Name: reaper.exe
Application Version: 3.7.4.0
Application Timestamp: 4d14d8ba
Fault Module Name: rhino2.dll
Fault Module Version: 0.2.0.9
Fault Module Timestamp: 4c814240
Exception Code: c0000005
Exception Offset: 0004db1a
OS Version: 6.0.6002.2.2.0.768.3
Locale ID: 2057
Additional Information 1: fd00
Additional Information 2: ea6f5fe8924aaa756324d57f87834160
Additional Information 3: fd00
Additional Information 4: ea6f5fe8924aaa756324d57f87834160