You need to compile a dynamic module like this
$ gsc 092.scm
That will give you 092.o1 This invokes the gsc-cc-o.bat script which calls gcc with the correct arguments. For example, you weren't compiling your module in single-host mode as single-host is a preprocessor flag.
$ time gsi 092.o1
SOLUTION = 8581147
real 0m27.238s user 0m27.014s sys 0m0.152s
We can add some declarations to your scheme file
(declare (standard-bindings) (extended-bindings) (block))
$ time gsi 092.o1
SOLUTION = 8581147
real 0m21.040s user 0m20.809s sys 0m0.192s
And finally you can remove safety but mzscheme is compiling with safety...
(declare (standard-bindings) (extended-bindings) (block) (not safe))
$ time gsi 092.o1
SOLUTION = 8581147
real 0m18.926s user 0m18.665s sys 0m0.172s