Hi Edward,

Thank you for your post here!

Thanks for reporting this problem to us. This is a known issue that has already been reported by other users, and our developers have already found out what caused the problem and a fix will be included in the next release.

In the meantime, to give you a bit more context about the issue, it seems that the problem comes up when the last surface selected has a comment in the Lens Data Editor. This is also the case when a red rectangle appears around the Last Surface to show there is a problem:

We didn't find any issues when selecting surfaces for last surface without a comment in the LDE. Please let us know if you saw a different behavior!

While our developers are working on the solution, I can think of two possible workarounds. You may try to delete any unnecessary comments from the LDE, and then you can continue using the IGNM operand. There seems to be no problem without comments on the last surface. We didn't find any problems using surfaces with comments as First Surface either. Alternatively, you can keep all your comments, and try to use the IGNR operand instead of IGNM. In this way, you cannot ignore multiple subsequent surfaces with only one operand, instead you will need to use one operand for every surface that you would like to ignore, but IGNR works with comments.

To provide you a more information about the bahavior of the IGNM multi-config operand, if you change the first surface, you'll see that all values of the operand for all configs are reset to zero. If instead you try changing the last surface, all values of the operand for all configs are set to whatever value is set for the active configurations. This is the intended behavior for this operand. This might help you finding further clever workarounds until the bug is fixed.

I hope this helps now, but if you have any further questions please let us know and we will be happy to help.

I will keep you updated about the bug report.

Best,

Csilla