For starters I recommend the usage of Config::Model, specifically it's
dpkg support for a consistently formatted d/control.
Its usage is documented in the Debian GIS Policy:
http://pkg-grass.alioth.debian.org/policy/policy.html#cme
This would fix the reported lintian errors:
E: qmapshack source: multiline-field maintainer
E: qmapshack: multiline-field maintainer
Secondly I'm not sure about some of the build dependencies.
You're currently using:
debhelper (>= 9.20120417~),
libgdal1-dev (>= 1.5.2-3) | libgdal-dev,
libproj-dev | proj,
If you don't intent to support backports, the following should be
sufficient:
debhelper (>= 9),
libgdal-dev (>= 1.10.1-0~),
libproj-dev,
>From the get-orig-source target in debian/rules I see that the ~repack0
upstream version suffix is used to denote the repacking done to remove
the .hg data for the Mercurial repository.
The suffix '+dfsg' is more common, but more appropriate if the repacking
is done to strip DFSG non-free files. That doesn't seem to be the case
so '+ds' is probably the better choice in this case.
With the recent enhancements in uscan it can strip files listed in the
Files-Excluded section of the debian/copyright file, you could use this
instead of the tar dance in debian/rules.
The current get-orig-source target can also be simplified by using `tar
--delete`. For an example see its usage in postgis:
http://anonscm.debian.org/cgit/pkg-grass/postgis.git/tree/debian/get-orig-source
Finally the package contains the qlandkartegt.menu file, which doesn't
seem appropriately named for qmapshack. And appears unused in the package.