[Cross-post] Notation Element Scaling and Sizing

I didn't know where the best place was to post this, so I'll put it here too. Sorry :(

Hey there!
I was editing a score of mine that uses clusters, so I looked for a notehead for that. Fortunately, cluster notation was present. However, I was unable to extend the lines coming from the noteheads as well as unable to extend the "connector" piece between the noteheads. This made it so I had to lump a bunch of tiny connector bits in between which is a bit tedious, and it ended up looking quite sloppy. Of course, I'm no artist.
Is there a way to scale/extend elements (like you can with arpeggios, pedal lines, etc. with those pink dashed lines, or those squares that allow me to drag the element to the desired size) that I pull from the master palette?

Also, I brought another element from the master palette: the Sostenuto pedal mark. It is significantly larger than the regular Ped mark. I want them to be about the same size.

I've already looked at the inspector while the element is placed in the score. Nothing. I've right clicked the element in it's sidebar palette, gone to "properties", and then played with the scaling function there, but that only scaled down the element icon in the palette.

Am I missing something? Can you help, please?
Thank you so so much!!