Unknown Error help in UDB

[DjDisk1996]

I am working on a map with about 3 wads merged using WADMERGE. I accidentally merged BTSX into it and am lazy to separate all the assets and MAPINFO from it by hand so have just been running with it. Randomly got this error log upon saving just a couple minutes ago and have no idea why it's happening. Any help?

Also: If anyone knows a way to separate all the BTSX assets from my wad while retaining my map (linedefs, sectors, etc) that would be nice. I only know how to do it by hand

[DjDisk1996]

Forgot to post the clipboard

here it is:
***********SYSTEM INFO***********
OS: Microsoft Windows 11 Home
GPU: AMD Radeon(TM) Graphics
UDB: R4132
Platform: x86

********EXCEPTION DETAILS********
Object reference not set to an instance of an object.
at CodeImp.DoomBuilder.Data.WADReader.Suspend() in c:\build\UltimateDoomBuilder\Source\Core\Data\WADReader.cs:line 218
at CodeImp.DoomBuilder.Data.DataManager.Suspend() in c:\build\UltimateDoomBuilder\Source\Core\Data\DataManager.cs:line 699
at CodeImp.DoomBuilder.MapManager.SaveMap(String newfilepathname, SavePurpose purpose) in c:\build\UltimateDoomBuilder\Source\Core\General\MapManager.cs:line 855
at CodeImp.DoomBuilder.General.SaveMap() in c:\build\UltimateDoomBuilder\Source\Core\General\General.cs:line 1478
at CodeImp.DoomBuilder.General.ActionSaveMap() in c:\build\UltimateDoomBuilder\Source\Core\General\General.cs:line 1438
at CodeImp.DoomBuilder.Actions.Action.Begin() in c:\build\UltimateDoomBuilder\Source\Core\Actions\Action.cs:line 269
at CodeImp.DoomBuilder.Actions.ActionManager.InvokeAction(String actionname) in c:\build\UltimateDoomBuilder\Source\Core\Actions\ActionManager.cs:line 426
at CodeImp.DoomBuilder.Windows.MainForm.InvokeTaggedAction(Object sender, EventArgs e) in c:\build\UltimateDoomBuilder\Source\Core\Windows\MainForm.cs:line 461
at System.Windows.Forms.ToolStripItem.RaiseEvent(Object key, EventArgs e)
at System.Windows.Forms.ToolStripMenuItem.OnClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
at System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.ToolStripDropDown.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ToolStrip.WndProc(Message& m)
at System.Windows.Forms.ToolStripDropDown.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

[Kappes Buur]

It should be simply enough to purge all BTSX assests from your pwad by using SLADE.