I've been building an AIO DVD for some time now and the ISO has slowly grown to 4GiB. I've also been looking for ways to update it with less effort. I've decided that with a little scripting I can probably make it much more customisable (e.g. pick and choose which OS variants I want today, which apps or app groups I want today etc.). I can do all of that if I'm prepared to copy around OS trees (Windows XP Pro SP3, Windows XP Pro SP3, Windows XP SP3+latest updates etc. etc.) and build a tree with the required customisations each time. But that's expensive on disk space and will take a lot of time. So I've looked around for a program that will create an ISO using a text file to tell it where to find each source file and where to place it in the DVD tree. CDBurnerXP *almost* fits the bill. It looks like its DXP "compilation format" will do exactly what I want. So my script can build a list of files for the DVD I want to build today and CDBurnerXP will create a customised ISO. Unfortunately it doesn't optimise identical files. (This means that for such files the data is written once and all the relevant TOC entries point to that same data). For that I still need CDIMAGEGUI. Now I could let CDBurnerXP run, have it build a 12GiB ISO, mount that with Daemon Tools and then have CDIMAGEGUI use that as a source and build the real ISO. That seems incredibly wasteful. So are there any scriptable optimising ISO creators out there? I've just asked in the CDBurnerXP forum if the optimising feature already exists or if it might be considered for the future. Looking at other questions in there, it seems fairly hit and miss whether I'll get an answer. UltraISO has the optimisation feature, but doesn't seem to be scriptable. Nero seems to have neither feature. CDIMAGE does the optimisation but burns a directory tree as-is. mkfsiso looks like it might be able to do some of this (along with duplicate file linker) but it achieves this by fiddling with the source tree. So is there anything out there which can do this?