It might depend on how much you need the original blocks and how many you’ve got.
You can always explode them all, all nested levels, with ExplodeBlock.
Change the layers you need to, and the re do the block you need. Problem is you will need to re insert tge block everywhere it has been placed. Probably this can be automated with Grasshopper.
That’s what i have had to do. But it is hardly efficient and it increases the size of the file considerably. I inadvertently exploded all the text and hatch also as it’s difficult to keep track of how many levels deep you need to explode to get all the nested blocks and change every object in the block to layer 0
exploding should not an option/solution. that goes againts the very meaning of blocks themselves.
Check this out:
One of the tools the script offers is to assign all block objects to a selected layer, including all nested blocks. You can also control which types of objects within blocks are affected. It’s a relatively old script but I think all still should work OK.
–jarek
If you make a copy of the entire file, do the ugly work with ExplodeBlock or SuperExplodeBlock to find out where the changes need to be made, then go back to the original file and edit the offending block(s) in place, that reduces the disruption.
Even that is an ugly solution to the problem though.
It seems as though there is no elegant solution 
Exploding blocks is a big no no for me. Nothing good seems to come of it.
I feel that Rhinos block manager needs an overhaul. The user interface is very counter intuitive which is very un-Rhino
That’s why I suggest making a copy of the main file (including all blocks) to find out where objects/layers/line types etc reside. You can just delete the copied file once you’ve found out what needs to be done. That way, you leave all of the block structures in the original file intact.
The root of the problem is that blocks (i.e. the block definition) shouldn’t really reside on a layer. But there isn’t a way around that
The gray overlay is the worst…
+1 on 2022.08.08. Imported an STP at work that was exported from Inventor by a supplier so pretty much all .iam assemblies became nested blocks and it is hell.
April 2023. After 8,5 years.
+1 for double-click and removing gray overlay.
+1 Here too, tired of having another instance of rhino opened, copy paste the block there, do the changes and bring it back in.
My humble suggestion is to offer this guy Block Edit New | Food4Rhino an adequate reward to sell his source code to you and implement it in WIP8…
+1 on 2023.08.08… still hoping to see the double-click option soon!
In Rhino 8 WIP, you can double click into blocks to edit them. It brings up the Block Edit window which shows the hierarchy of nested blocks and you can select a child and then double click into that and edit it as well.
Ideally you could double click into the first level (parent block) and then double click into the child block(s) without having to touch the Block Edit window at all though.
Hello Michael VollrathRegular
Rhino 8 Beta double-clicking doesn’t work fine with imbricated blocks
Has no hide all option
I hope McNeel us planning to improve BlockEdit.
I installed, replaced McNeel’s plugin (renamed) by Block Edit New (by wucl12)
Food4Rhino – 24 Sep 22
Could you please have a look ?
He has done a very good job
I wouldn’t like to steal his work, but I would for sure, and many people I think, would appreciate having these options in native Rhino 8
If not I will donate
Works really fine.
Best regards
Only there is a problem if you have bad objects:
Not noticed any problem
What kind of “bad objects” do you have ?
Here a simple example - two door plates in a block. The right part is a “bad object”, it has an invisible tiny error and I used this block over weeks without problems for 3D-viz. But now it is removed by Block Edit New.
Also strange, you don’t have a chance to edit the block and to repair it, since it is immediately removed if you edit the block. Only explode … helps.
Bad object block.3dm (1.1 MB)
I wrote to the plugin developer but he dosn’t answer.
I can’t use the nice plugin anymore. It push me to repair bad objects but I don’t know how to repair it. For example I got an airplane seat from my client and anything is fine since weeks. But the plugin removes all bad objects and destroys the model.
Can someone please send me the original BlockEdit.rhp of Rhino 7 and 8 please? The plugin removed the original BlockEdit.rhp and I have no backup. An install repair doesn’t help.
A new version is released and now it works perfect, no bad object issue anymore. 
And for moving back to standard Block Edit there is an uninstall function on the installer.
