How to prevent OSS from changing the Default OS to one on a drive moved from another system

Hi

I quite like OSS as a boot selector programme, but there are one or two things about it that I find irritating. One of these is that OSS decides to change the default Operating system from the current setting (of Windows 7 for example, that's the native OS on my main PC) to whatever OS happens to reside on another disk that I might connect to the PC.

This seems to happen whether it's a bootable flash drive (that I'm trying to set up as a server recovery key for my WHS box) or a hard drive from another PC (from which I'm trying to do a bit of data recovery).

Instead of just assuming that I want to boot to the new OS that OSS has just found, can I set something to tell OSS to never automatically change the default OS? I currently have OSS to boot to the default OS without showing its menu, so it's particularly annoying to have it decide to change this without asking.

I know that I can also set OSS to display a menu of the available Operating Systems at boot time, for example, but most of the time I'll boot into the default OS so I have the menu turned off. Could OSS be set to only display its menu of available operating systems at boot time, when a new hard drive or operating system is detected?

Thanks.