http://www.ianparmenter.com/hcutils/map.jsp?map=AVO

If I have a figure in space Q11 (on the rooftop), can non-elevated figures target that character on the diagonals?

Thanks.

Yes.

According the the Fantastic Four Rule book (pg. 12 "The Rim")

A square with a red line running through it (marking the
boundary of an area of elevated terrain) is on the rim of elevated terrain. If
an elevated character is on the rim of elevated terrain, it can make ranged
combat attacks targeting grounded characters and be the target of ranged
combat attacks made by grounded characters. If the line of fire between a
grounded character and an elevated character crosses any elevated square
not on the rim of the elevated terrain, or any square on the rim not
occupied by the target character, the line of fire is blocked.

since the straight diagonal lines wouldn't cross another elevated square they would be able to draw a line of fire from a straight diagonal

yes , and i love tht map!!!!