DSS crashes when producing master flat

[Demonperformer]

Running DSS v 3.3.2 on win7 machine. Calculating master frames before processing all the lights (one light added to the mix to enable the program to calculate the masters). Master bias, dark & darkflat produced successfully. Trying to produce a Masterflat produces an error -

Problem signature:
  Problem Event Name:    InPageError
  Error Status Code:    c000009c
  Faulting Media Type:    00000003
  OS Version:    6.1.7601.2.1.0.256.48
  Locale ID:    2057
  Additional Information 1:    0a9e
  Additional Information 2:    0a9e372d3b4ad19135b953a78882e789
  Additional Information 3:    0a9e
  Additional Information 4:    0a9e372d3b4ad19135b953a78882e789

When I click on the "check online for solution" option, it produces another (different) error -

Problem signature:
  Problem Event Name:    APPCRASH
  Application Name:    DeepSkyStacker.exe
  Application Version:    3.3.2.0
  Application Timestamp:    4b0041ae
  Fault Module Name:    ntdll.dll
  Fault Module Version:    6.1.7601.23418
  Fault Module Timestamp:    5708a73e
  Exception Code:    c015000f
  Exception Offset:    00084383
  OS Version:    6.1.7601.2.1.0.256.48
  Locale ID:    2057
  Additional Information 1:    dd88
  Additional Information 2:    dd884736192fe9d4c02c5a3f0dbca5d7
  Additional Information 3:    01ad
  Additional Information 4:    01adf6844477cfa12f820665c93f69e7

I have tried the process several times and the errors reported are identical. I then tried running it in XP(SP3) mode, with identical results. Unfortunately, I am not fluent enough in "Computer" to be able to translate the above into English.

Any suggestions as to what is happening, why and how to solve it gratefully received.

Thanks.

[Steve Ward]

What camera are you using ?

Newer Canon CR2 RAW files need DSS 3.3.4    ( EOS1100 onwards ) 

[Demonperformer]

ZWO 1600 mono cooled, FITS files. I would have thought any problem with the files format would have prevented the darks, darkflats and bias too?

Thanks.