As you probably know the rotor plugin is rather buggy by now as it has more patches than code. It would be not be necessary if vdr had an option ´Enable GotoPosition ´ and if enabled it sent the diseqc command E0 31 6B XX which means ´First rotor go to stored position XX´ when changing to a channel on a different sat position.
This way it would be posible to use an external program such as xdipo (GPL) to store the orbital positions in the first place and then just configure diseqc.conf for vdr use.
#my diseqc.conf
#S19.2E is the first stored position S19.2E 11700 V 9750 t v W15 [E0 31 6B 01] W25 [E0 31 6B 01] W15 t S19.2E 99999 V 10600 t v W15 [E0 31 6B 01] W25 [E0 31 6B 01] W15 T S19.2E 11700 H 9750 t V W15 [E0 31 6B 01] W25 [E0 31 6B 01] W15 t S19.2E 99999 H 10600 t V W15 [E0 31 6B 01] W25 [E0 31 6B 01] W15 T
#S13.0E is the second stored position S13.0E 11700 V 9750 t v W15 [E0 31 6B 02] W25 [E0 31 6B 02] W15 t S13.0E 99999 V 10600 t v W15 [E0 31 6B 02] W25 [E0 31 6B 02] W15 T S13.0E 11700 H 9750 t V W15 [E0 31 6B 02] W25 [E0 31 6B 02] W15 t S13.0E 99999 H 10600 t V W15 [E0 31 6B 02] W25 [E0 31 6B 02] W15 T
#S5.0E is the thirst stored position S5.0E 11700 V 9750 t v W15 [E0 31 6B 03] W25 [E0 31 6B 03] W15 t S5.0E 99999 V 10600 t v W15 [E0 31 6B 03] W25 [E0 31 6B 03] W15 T S5.0E 11700 H 9750 t V W15 [E0 31 6B 03] W25 [E0 31 6B 03] W15 t S5.0E 99999 H 10600 t V W15 [E0 31 6B 03] W25 [E0 31 6B 03] W15 T
#plugins/rotor.conf S19.2E = 1 S13.0E = 2 S5.0E = 3