Show Cue System

Hello big brain.
I have this cue sequence.
Q1 Audio File Cue
Q2<1> Fade Q1 down.
Q2<2> Audio file cue.
(This small sequence start some music and then Q2 fades the music down and start a voice over.)
When I try and delete Q2<1>. The fade. I get this error message.
Error Invalid procedure or call.
SCS 9.4.6.
Proc name = public node click
Cue file = c:\........(file name)
When I press OK, the sub cue does delete and I can continue. No crash.

Any thoughts why I'm getting this error message.
Thanks
Adair

Sorted that out, Adair. Will be fixed in the next release. The error occurs for any cue that has two sub-cues where you delete the first sub-cue. The error is raised on re-displaying the cue list - no damage is done to the cue file.