access custom properties in mechanical browser

Hi Team,
In the panel of the component insert option in the mechanical browser of BricsCAD, there is a "custom properties" node(see picture in attachment file). I have searched a lot of information but have not found how to read and write it through a programming interface
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#2. Get material
There are two types of materials. If you want to assign e.g. an Aluminum or a Wood material to the component, you should associate a material from Mechanical Materials, which is different to the classical Material.
You can read the related Help: help.bricsys.com/hc/en-us/articles/360006522234-Components-and-Component-Inserts
Assign physical materials to components

- if you add a component definition, e.g. a box and run BMMECH, then assign a Wood material to it, you can get its Mechanical material with:

_AcMec.ComponentDefinition compDef2 = _AcMec.ComponentDefinition.GetComponentDefinition(per.ObjectId, false);
ed.WriteMessage($"\n => compDef2.Material='{compDef2.Material}'. ");
If your component has many boxes with different wood based materials, you might set the material at the component level, e.g. let's say 'Timber Sub-floor'
- if you BMINSERT that in a new main drawing, I see ComponentDefinition.Material is empty when using the default BricsCAD settings. A solution can be: temporary explode that block reference and then select the nested box Body_1 (you can see that nested component, in the MechanicalBrowserOpen panel) to get the Material Wood. That could be made in a transaction that would be aborted in the end, or the drawing could be closed and reopen to undo that explode.

I noticed on a related, recent SR 167025, that:
- if I set MECHANICALBLOCKSOPTIONS=1 => then insert the component: compDef.Material='Timber Sub-floor', which is the global mechanical material for the component definition.

You might have a look at %ProgramFiles%\Bricsys\BricsCAD V24 en_US\API\dotNet\CsBrxMgd\CsBrxMgd\MechanicalComponents.cs
If official samples are not added, you can just test/experiment/implement the needed functionality based on the existing classes/methods/properties.

Here is a relevant code snippet attached.