Lifting Lugs in COMPRESS

[ColinPearson]

Hello All:
I'm new to COMPRESS but fairly handy with software. I thought I was cruising along just fine until I went to proceed with Attach>Rigging/Lift Lug>Rigging Analysis and I get the following:

"Lift lugs are not in a valid combination for use with Rigging Analysis. You may still specify a rigging analysis, but the lift points will not be synchronized with lifting lug locations."

I've got a one cylinder vessel, elliptical head, a couple nozzles, cone transition, support skirt/base ring and a couple stiffener rings. I don't immediately see anything on the trunnion dialog box that is out of what COMPRESS will allow, Googling has turned up dry and I don't see the issue discussed in the Help literature.

Anyone know what this means? I've attached the main file.

Thanks folks!

 

[ozPE]

I am not 100% sure what the question is but I'll have a go at it anyway.
Lifting lugs may involve detailed analysis of load path and stiffness... requiring separate design of lugs.

 

[ColinPearson]

Thanks for getting back to me. I'm just wondering what the error means?