If you click multiple times in the virtual console while WinPE is booting the mouse and keyboard will work.
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I am running on 1.45.45 and have the same issue. I don't think downgrading the idrac FW fixes anything. I heard WinPE5 support isn't officially being added until late 2014.
FYI - a reflash is not necessary but only a RACRESET. In order to do this from the idrac webpage click troubleshoooting -> diagnostics -> Reset idrac. This still takes a couple minutes but does temporarily fix the issue.
I was able to fix this applying 1.51.52 FW