How to create lined pipe

[PADAGAX]

I have been fighting lined pipe, specifically PTFE lined pipe for a while now. I'd like to know how to create flanged (lined) pipe that works as follows:

• Variable in length
• Iso that includes the 'flange-lined' block for end connections
• Does not include the information for flanges in the iso BOM table.
• Allows placement of in-line flanges to break up spool size as req.
• Has LFL end types for ease of connection setup
• Omits welds for pipe runs and flange connections on runs of lined pipe

Using the method in FP-001 (image) I can get a decent result, but in-line flanges do not work without the addition of a spacer to simulate a gasket/break and the need for a new fixed pipe.

The pipe's flange skey gets assigned to the pipe layer which increases the lineweight of the flange and makes it overlap the fitting flanges making them illegible. The fitting's flange is assigned to the symbol layer. 

I've tested this with different configurations and a few things don't make any sense. I don't know how 'FPFL' (recommended by another user) works as an skey because it doesn't exist in my skeyblockmap file. The iso symbol type in the catalog part has to be included as 'pipe-fixed' or it doesn't work the same. 

I have used the older 'PIFX' designator, modified the xml to add skeys or change them around, looked for ways to omit items from BOM and many many more unfruitful methods. I'm at a loss, and frankly.. I'm probably overcomplicating things. I want to stay away from third party addons resistoflex and the like as they don't get stellar reviews in the first place.

I recently switched to 2024 and was hopeful when I ran some normal pipe and added a custom part flange with an skey for lined flange. I was able to create a new connection type for LFL using only bolts, but unfortunately the BOM generates with the flanges and welds which I don't need. 

If pipe is only a polyline on an iso, how is it's presence on an iso determined? Where is that happening..

What is the purpose of the 'FixedPipe' block?

How does the FixedPipeFlange get added to both sides of a fixed pipe run? Is it the boolean true/false on end connections. Further, how is it creating an entirely new block for iso left and right when used by isogen?

Is there a method for omitting things from the BOM without scripting other than marking as existing?

I'm about ready to pull my hair out, so I would like some advice on workflow and existing proven methods for creating what should essentially be a simple thing. Thanks in advance.