Concise problem statement:
DRL files may contain holes with negative coordinates. While generating Fabrication output DRL files EasyEDA overwrites the first leading "0" with "-" sign when hole coordinate(s) is (are) negative. When such DRL is viewed using gerber-viewer.easyeda.com all holes with negative coordinates are displayed 10 times further away from the origin than supposed.
Steps to reproduce bug:
Load any fabrication output with DRL file(s) containing holes with negative coordinates.
Watch the holes with negative coordinates displayed far away from their expected locations.
Holes displayed at their normal locations as specified in the original design.
Open DRL file(s) with any text editor, find all "-" and replace with "-0", save and reload the fabrication output. Watch the holes displayed in their proper places (unless the design is larger than 10' in one or both dimensions).