Hi Norbert, Hope you are resolved your issue.
but i see at there has three issue.
1. as Carlos link.
IDEMPIERE-1512 it's miss support font in server when generate report.
2. difference char (but in your attach file i don't see difference),
maybe it's by your font you choose miss glyph of some character, but other font in same family has, and it use for replace.
3. some character render as sharp. it's by design of build-in report. every sentence contain character out of ansi code is render as sharp
it help resolve case miss font in client and not need embed font.
just issue-3 is must change code, maybe add a user preference for choose between:
+ render normal, client will install miss font
+ embed font
+ same as current design