I opened dragonbox/appdata/dbpInstaller_sebt3/cache/dbpInstaller/packages-pyra-handheld.com-repo-needdata and removed SlayTheDragons, saved and then dbpInstaller worked. It seems like I used Windows line breaks.
So the problem is SlayTheDragons. But I cant remove it myself from the repo via the web interface. When I try to edit it I get an error:
I tried to upload a bugfixed version 1.3 of SlayTheDragons with Unix linebreaks. But the old version 1.2 still exists. I guess because it has a different ID ("SlayTheDragons" vs "SlayTheDragons\r")
So I still think that sebt3 or somebody with access to the server has to fix it.
I'm really sorry for the hassle!
Info for sebt3 or whoever can access the database: I recreated the problem on a local installation of the DBP Repo. Seems like the following problematic database objects have been created:
select * from dbpackages where str_id like '%\r%';
select * from package_versions where path like '%\r%';
select * from archs where name like '%\r%';
And I guess some other tables have foreign keys to the dbpackages table (packages_maintainers, repo_activity).
The packages-pyra-handheld.com-repo-needdata still contains old information. I tried to upload a new version 1.3.1 of SlayTheDragons to force it to renew the list. But it is still the old list. Maybe it caches it for some time?
When I manually delete the folder appdata/dbpInstaller_sebt3 (to force dbpInstaller to get rid of the old cache) everything seems to work.