This is a normal behavior since you fill in the custom properties of your parts, you would have to fill in the one of the assembly for them to appear in the MEP of the assembly...
My message wasn't clear enough, but I'm trying to fill in the property of the nomenclature and name the block.
Let's take for example an assembly whose description is "bike": in the name, where I would like it to be written "wheel" as entered in the property of the component, I find the designation "bike" and this, on all the components.
I've tried all sorts of settings to bind properties, but I can't find the properties I created in the component-specific drop-down menus.
Normally everything is linked, otherwise you have to modify your nomenclature so that it fetches the information from your parts and once it has been modified you will just have to save it...
You place yourself in your 3D You insert the standard nomenclature of SW (bom-standard.sldbomtbt if I remember correctly) You right-click on the header of a column You insert a new column (right or left) In the window that just appeared: Column Type: Custom Property Property name: You select a property name (of your rooms) that you want to appear in this column.
You insert as many columns as you need to have the information of the parts in your assembly.
Don't forget to save the new BOM configuration at the end. Selects the BOM In the top left corner right-click on the square with the arrow cross Select save-as Saved in .sldbomtbt format. (save your new nomenclature in a directory where you can find it easily)
Your new BOM can also be used in a drawing. Select a view of your assembly and insert your new BOM configuration