It should probably know about more paper sizes.
Errors sometimes report inaccurate line numbers.
Gri only draws line segments which connect two points each of is inside the axis frame. Note, however, that postscript clipping works correctly, and that it is recommended anyway. Bug reports help make Gri more reliable and useful for all users. Bugs in the current version are likely to be repaired, while the probability of my repairing bugs in previous versions is low. I invest in the future, not the past.