Block explosion problem

I have a simple block - it's a bush symbol made up of a series of joined arcs. What I want to do is to explode it, but for the arcs to remain joined following the explosion. I thought it was simple enough to do by just joining the arcs before defining the block. In theory this works fine, but when I insert a drawing into my template (which contains my block defined in this way) and explode the block the arcs are exploded from each other as well. I don't understand how this can be! Any suggestions?

Just to help clarify, I've attached a couple of drawings:

SYM10-A contains the block as defined in my template. You will see if you explode it that the arcs remain joined as intended.

SYM10-B contains the same block, but from a drawing inserted into my template. The block has the same name, so it should take on the properties of the block as defined in the template. However, you will see if you explode it that the arcs are now individual segments of ellipses. Wierdly, though, if you treble-click the block in this drawing to go into the block editor you will see that the arcs are joined, so why are they not joined when I explode it????

SYM10-A.dwg

SYM10-B.dwg

Hey rooster

Had a look at both drawings.

SYM10-B seems to be inserted at a non uniform scale.

The X & Y scale is 4 but the Z scale is 1

Updating the scale to match seems to allow SYM10-B to explode correctly

Learn somthing new every day...

Thanks jammie - I'll look into that & hopefully it will solve the mystery!