[smw]

[...] If you tap on a stamp in the list, then tap on it again, you'll see an option to "Reset all lists". This will load the default stamps configuration file and you should then see the repeat stamp you are looking for. [...]

As far as the second issue, if you tap the second icon in the toolbar to collapse it, does that give you access to the stamp window so you can move it? [...]

Thank you!  This solved both my issues.

Although, like Palosanto, I'm now in a position where the Standard set has both repeat symbols but the Jazz set still has only the repeat start. That's not a problem for me (I generally use the Standard set anyway), but it's something I thought I should mention in case you weren't aware.