I have FILR patched to 450

When I startup the filr client I see the following in the client log.

2016-07-01 08:51:59,835 [MainThread] [INFO] Filr 2.0 (228) is starting. (aca)
2016-07-01 08:51:59,835 [MainThread] [INFO] Python version 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] (aca)
2016-07-01 08:51:59,835 [MainThread] [INFO] Local timezone offset: 10.0 hours (aca)
2016-07-01 08:54:27,569 [MainThread] [INFO] Retrieved file sync directory: D:\Novell\Filr Storage (aca.filesync2.monitor)

My issue is not that it takes 2.5 minutes to start doing anything, its that while this is happening, everything else (groupwise, explorer, firefox for example) goes unresponsive (not responding). Once it reaches this point, everything starts responding.

Yes I have a lot of data in my Filr Storage, which is on a relatively slow sata drive, resources show 18.1 % cpu in filr.exe (32 Bit) and 18.1 % in Service Host: Local System (17) - I assume the 2 are related, as when one stops, so does the other.

I don't believe it should be blocking the system whilst its doing this.
Anyone got any suggestions ?
Thaks in advance