Gradle build cross-platform - trouble with Saxon 6.5.5 params under Windows

[Peter Desjardins <peter.desjardins.us@gmail.com>]

Hi! I have a working Gradle build system that transforms DocBook 5.1
(using an assembly) to a few output mediums. I'm using Saxon 6.5.5 and
the DocBook XSLT 1.0 stylesheets (latest version). When a new writer
chose to use Windows, the Gradle build broke when she ran it locally.

Problem #1 is that the Gradle exec task that assembles the DocBook
assembly using Saxon 6.5.5 won't work under Windows. Saxon complains
that there's "no output file name." Gradle has a terrible problem
consuming the "-o myoutputfile.xml" argument.  If I present the "-o"
argument separately, Saxon claims that the output file name is
missing. If I present a "-o myoutputfile.xml" argument, Saxon
complains that  "-o myoutputfile.xml" isn't a recognized argument. Has
anyone built a Gradle Exec task that runs Saxon 6.5.5 on Windows? It
works just fine on Linux and MacOS.

Question #2 is: Has anyone had trouble using Saxon9HE with the DocBook
XSLT v1.0 stylesheets? The way the arguments for the later version of
Saxon are structured work much better with Gradle.
(-o:myoutputfile.xml.)

I'm considering switching to the DocBook XSLT 2.0 stylesheets to work
around this problem. That avoids mixing Saxon9HE with the DocBook XSLT
1.0 stylesheets. Has anyone had any trouble migrating to XSLT 2.0?

Thanks for your help!

Peter