Just "inherited" a 2007 iMac and loaded Yosemite (OS X 10.10.1)
First thing I loaded LO 4.4.0.2, and then 4.3.6.2 and the current
(2015-01-21) 4.5.0 master.
Steps couldn't be simpler. In fact parallel install is done almost the same
as with the Windows .msi packages
Put which ever of the installs into /Applications just like any package
install. Drag and drop there once the .dmg is downloaded and mounted.
Launch by double clicking the folder in /Applications.
For the additional installs, they could go into /Applications as well just
with different names.
But they can go anywhere. For example onto user's Desktop, Documents,
Downloads etc... just mount the downloaded .dmg package and drag the
LibreOffice or LibreOfficeDev .app directory object to where you want it to
reside. It does not need to go into /Applications.
Then use Spotlight to find the bootstraprc file and edit it in TextEdit.
Just as with Windows or Linux builds, edit the
"UserInstallation=$SYSUSERCONFIG/LibreOffice/4 "to be
"UserInstallation=$ORIGIN/../Data/settings"
The $ORIGIN variable is parsed internally by LibreOffice and then creates
the entire user profile within the app package, in the example
"Data/settings" but the directory names for the user profile can actually be
anything you like. They are fully structured profiles and are portable.
When ready to launch the build, open the .app folder with Finder and locate
the soffice executable and Control Open it. You can create an app launcher
for it if you don't want to dig down into the folder every time.
Easy as pie... I had all three flavors running simultaneously and could do
side-by-side comparisons of the UI.