thanks for logging this, we are looking into it at the moment and will update you with our findings soon.
Try inserting the -NoSignatureCheck flag in the Export-EsxImageProfile line as shown in the below example:
PowerCLI c:\vm> Export-EsxImageProfile –ImageProfile Image1 –FilePath ESXi-6.0.0-2494585-
aacraid-b41024.iso –NoSignatureCheck -ExportToIso
I was unable to create a ESXI6 ISO containing drivers for my Adaptec 6805 card due to the error you reported. All other examples on the web omitted this flag, though the examples were posted prior to the release of PowerCLI 6.3. I found this argument in Adaptec documentation buried within the zipped driver folder and inserted it, then created the ISO with no issue.
Hope this helps.
According to the Release Notes this issue has been fixed in PowerCLI 6.3 R1 Patch 1.
So far I have not got any feedback from concerned users. Can anyone who has experienced this issue confirm that it is fixed in Patch 1?