Question : Problem: Citrix and subnets

We have a presentation server that resides on a 192.168.1.0 subnet
We are getting several issues with home users, particularly with BT homehubs that are unable to connect to the published apps / desktop as their routers are set to the same subnet, as a result of this they cannot connect.
We are using VPN1-Securemote on the users PC's to establish a secure connection.

Answer : Problem: Citrix and subnets

So you can probably resolve this by having those specific users come in through the Internet, not the VPN.  I would only suggest this if you had the Secure Gateway set up (it comes with Citrix Presentation Server).  This would give you SSL security as well as the standard Citrix ICA encryption.  The problem obviously is that your users know of a router that conflicts with where you are trying to send them.  Going through the Internet instead of an IPSec tunnel will make it come from a different address.  Have you tried a "route add" to statically define the resources in the remote network  you are trying to get to?  
The other thing you could consider (much more work) would be to configure your Citrix farm to sit on another VLan.  I would take the Secure Gateway approach were it me having this issue.