Using latest Lazarus (1.4.2) I can't open old laz reports from about a year ago.
Get this error:
Unable to stream MainReportMod:TMainReportMod.
Illegal character
If I chose ignore the report opens empty except for one plain text memo field.
I know this happened about a year ago with version 1.2 as well, I can't remember what I did to fix it.