FXCM is an installable platform if memory serves. You will need to install "Wine" from synaptic package manager. Then you will be able to run windows programs. I use Oanda which utilizes a java platform which functions flawlessly on Linux.
What version of Ubuntu are you using? This way I can direct my answers more accurately. There are changes from release to release.
If you are using 10.04 or earlier you will be using synaptic. 11.10 and later you will be using the software store. Though you can use the store to install synaptic.
I tend to like synaptic better as it seems to find dependencies better.
Also if you install "Ubuntu Tweak" much of this can be done from that program.
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