crash in pspad build 2521

Here is the crash log:

Exception description:
This crash occurred during Save. I had 8 files open, and had edited and saved this file many times before this.
Pspad had been open for about 6 hours. This is build 2521, I had been using it for weeks now, this is the first time this crash has occurred.
OS: Win7 64bit

Access violation at address in module 'pspad.exe'. Read of address .

Exception class:
Exception address:
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Stack list, generated 01/08/2015 15:14:53

 

Please send such reports to Jan by mail (for address see PSPad > Help > About)

 
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Program : C:\pspad\pspad.exe 4.5.9 (2521)
System : Windows 7 Professional x64, Version: 6.1, Build: 1DB1, Service Pack 1
Processor: Intel, Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz, 2400 MHz MMX
Display : 1920x1080 pixels, 32 bpp
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Active Controls Hierarchy:
TPSSynEdit ""
TfChildEdit "_3"
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Edited 1 time(s). Last edit at 2015-01-30 21:47 by Stefan.

PsPad crashed again last night; this time I wasn't able to capture the debug dump, because the crash-info dialog was *also* hung, and I could not interact with it.