Select all the elements, cut. Under modify, Paste, choose "aligned to selected levels". Choose Level 1.

Or, you could select all, and choose Level 1 in the properties under Base Level.

I've never tried it for 200 elements, but it should work.

Since they are all on the same elevations, just different levels, the connections (in theory) shouldn't be affected.

Problem is selecting just the elements that are associated with level 1 and not main level. As I'm typing this it dawned on me to try a view filter, by base constraint... is that possible? Off to see.

You don't have to. Just select them all. If they are already on main level, it should just replace them.

Actually, as I'm typing this, I think it will change the element ID, which may mess up the connections. Might want to try it and see.

Filter isn't going to work I think... can't create a filter for workplane (unless I missed it).
BUT: you could do this:

1. Delete level. You'll get an error about deleted stuff. Expand the error box, and export the whole thing to a xml file.
2. Open the xml file, select all element ID's, paste to notepad. Make it look like this:

IDnr, IDnr, IDnr, and so on. No returns or anything.

3. Cancel the delete-action (or undo). Now go to Manage > Select by ID. Copy/Paste everything from your notepad list.
4. Now all elements are selected, cut to clipboard and paste on the correct level.
5. If this doesn't work (because your ID's will indeed change), you'll need to manually select them all and use the Edit Workplane button to rehost.

Good luck!

Thanks for the advice, turns out view filters did the trick, and with minimal heart burn. Also, when deleting the level I don't a list of elements deleted just the views, is there something I missed?

For those who may run into a similar problem here's how we went about fixing it. First I moved the level down and accepted the lost connections, did a selection across the whole model and used the filter selection to see what categories I needed to work with. Luckily it was limited to just five. Undid the move and created a new 3D view. Did a selection box across the whole model and noted the total number of elements in the model - used for reference once I deleted the levels to be sure no elements went with them.

In the new 3D view I isolated each of the five categories one at a time and created a filter for each category where "base level" did not equal "level 1," and unchecked visibile. This left only the structural columns, for example, with the base level of level 1 visible, select them all and change the properties. Rinse Repeat. However as Martijn pointed out, for some reason when we got to walls we could not filter by workplane. A little more effort for those walls having to select them independently, some braces that needed to be rehosted, and a few model groups that needed to be edited within the group editor, but overall things went smoothly.

May not have been the fastest, but I am confident we got everything, and to be sure did a full selection after deleting the levels and matched the total number of elements. Now for a :beer:

Right, stupid mistake :banghead: I tried to create the workplane filter for the wrong categories (obviously).

About the error message: did you get a message when you moved the level? I might have been fudging up the two...

There we go, moving the level did it. I knew I'd seen a list at some point. Think I'd still end up having to use the view filters because not every element is disconnected when moving the level... however if Revit did give a warning for every element deleted when deleting the level your workflow would be perfect, in fact you could do away with the copy/paste all together if you could select by ID and then filter selection to individual categories. Thought... would each deleted element be listed in the journal file?

Yeah, it would be nice if it did give a warning about all elements deleted. Irritating bug if you ask me. Could care less about the deleted views. That seems quite obvious. It's the elements on the levels I want to know about...

You can select by ID and then filter to categories. Do a select by ID and look in the bottom right corner of your screen. There's a little funnel there which will show you all categories you selected. Check and uncheck as you please...

Anyway, don't know about journals, tend to stay as far from those as possible...

an irritating bug indeed!
does anyone know if there's API add-on to delete level safely?
in terms of (element and unique) IDs, seems moving group around will change IDs for both group and elements inside that group?! i didn't notice it before, well, IDs should not be changed within current Revit session, any logic / reason behind it? and how to avoid it? i mean keeping IDs unchanged.
thanks.