32bit and 64bit versions

I downloaded the 32 bit version of Ardour 3.I wanted to try it on a 32 & a 64 bit installation.I assumed that the 32 bit would work on a 64 bit system.Do I have to pay again to also DL the 64 bit.I tried to but when I select the version & the amount and then click the continue button.nothing happens.It seems like the continue button has no link attached to it.

@CraigPID: contact me via email help@ardour.org