specifying different subsets for the same config file

[igordot]

I would like to plot multiple BAM files using different regions. For preset regions (tss, genebody, etc.), I can specify them with -R without having to modify the config file. However, if I want to use custom regions, it seems that I have to specify them in the config file, so I need to create a new config file for each set of regions. Is that correct? Is there any way to specify custom regions on the command line without modifying the config file?