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Yesterday a Linux Installation Party was part of our workshop program of the
working group open source at our university.
Our students need Windows in their first 2 years for programming. That's the
reason for dual boot installations of their laptops.

The openSUSE installation (without expert partitioner) reduces the Windows
partition too much. After the execution, we had only 70 GB for Windows left.
Visual Studio and our programming homework (incl. examples by professors) need
more space in 1.5 years.

We had to use GParted after that.
The idea by our Students:
Give a warning, that Windows will be reduced to 70GB. The user can choose more
space for Windows in the partitioner and openSUSE space will be reduced
automatically then.

Reproducible: Always

Steps to Reproduce:
1. Take a pc/ laptop with Windows.
2. Start openSUSE installation on it.
3. The partitioner can find the Windows partition (without Expert partitioner).
4. The Windows partition will be reduced to 70GB.
5. The openSUSE installation will be finished successfully (with more space
than needed).
Actual Results:  
After the dual boot installation (without Expert partitioner), the Windows
partition will be reduced to 70GB and openSUSE receives more space than needed.
We had to repartition with GParted after the openSUSE installation.

(good thing: dual boot installation is better and easier than on Ubuntu :) )

Expected Results:  
The openSUSE installer doesn't reduce the Windows partition so much. It would
be great, if you can choose the size of the Windows partition after openSUSE
has found the Windows partition and openSUSE receives all the rest of the hard
disk.