I got the same error, with pretty much the same text output.
NO colon or any special characters were used; I placed a directory in the root of my drive and asked for the project to be saved and rendered there.
the unix style path name:
/Volumes/Digital\ Est/Hugin/*project and output file in this folder*
I downloaded the latest 0.7.0 from here ( http:// hugin.sourcefor ge.net/ download/ ) and tried again.
I got the same error, with pretty much the same text output.
NO colon or any special characters were used; I placed a directory in the root of my drive and asked for the project to be saved and rendered there.
the unix style path name:
/Volumes/Digital\ Est/Hugin/*project and output file in this folder*