unpartioned space of 977 KB causes problems

I try to install reactos on a system with an existing partition starting at sector 2048:

Index  Start         Length        Hidden      Nr  Type  Boot  RW

-----  ------------  ------------  ----------  --  ----  ----  --

    0          2048      20969472        2048   1     b     *   N

    1             0             0           0   0     0         N

    2             0             0           0   0     0         N

    3             0             0           0   0     0         N

During setup an unpartioned space of 977 KB is shown. unpart1.png
It is not possible to create a partition, because the size must be entered in MB, and it is less then 1 MB. A partition of 0 MB cannot be created.

When I press enter on the unpartitioned space, an error message is shown that a reactos partition must be at least 450MB. unpart2.png

Back in the partition window, the unpartitioned space is now shown as a new partition, which is drive C:. unpart3.png

After selecting the 10 GB partition (now drive D:) to install reactos on, a dialog is shown how to format it. unpart4.png

After choosing quick format, an error message is shown, and the computer has to be rebooted. unpart5.png

After the reboot, the existing partition now uses slot 2 in the MBR:

Index  Start         Length        Hidden      Nr  Type  Boot  RW

-----  ------------  ------------  ----------  --  ----  ----  --

    0             0             0           0   0     0         N

    1          2048      20969472        2048   1     b     *   N

    2             0             0           0   0     0         N

    3             0             0           0   0     0         N

This caused the problem I describe in CORE-11330