Windows 10 x64
i7-6700 @ 4.00Ghz (4 cores / 8 processors)
16GB Ram (high speed gaming)
Affinity Photo v1.10.1
Same issue with crashing while batch converting several CR2 files to JPEG (or really any exported format). While monitoring the conversion process, I noticed the CPU spiked and maxed out, as well as RAM through the roof.
The underlying issue is Affinity Photo is defaulting to "parallel processing" (small checkbox in the lower left of the batch convert UI) and the code is not correctly managing the parallel process.
Once I disabled "parallel processing", the conversion process completed without error. And actually converted as fast, if not faster than parallel processing when testing with small batches, re: small batches of 5 or so images did not crash the system.
I haven't tested this theory (and not going to; Affinity needs to do their own testing), but I suspect a batch process with more images than processors available, or some multiple of cores/processors) is the culprit in the code base.
Cheers!