Self Extracting Zip creation file size limit?

I've been creating a Self Extracting Zip using Zip-2-Secure-Exe, and I quite like the program. But I do run into a particular problem: it seems that overly large files throw errors when they are being zipped.

I've been trying to zip up all of the Runtimes that my setup file will use alongside my setup file, but one of them (about 80 MB) always throws this error:

appendToSimpleArchive:
WindowsError: The process cannot access the file because it is being used by another process.
failedToDeleteFilepath: .\ckz_6G8N.tmp
--appendToSimpleArchive
Failed to append Nth file/directory to EXE.
fileOrDirName: Runtimes/32 bit/CRRuntime_32bit_13_0_11.msi

Is there any limitation on file size that is getting in the way, or is it something else entirely?