For example, if you want to get intergenic sequences for specifi activity lets say all the gene relatad to "Magnesium" in all bacteria: First select the checkboxes for:
"product" or/and "gene" and other fields like "start", "end", etc. if are required in the "cds" section (because this is where you find the information on chromosome)
"DNA fragment" or/and "description" in the "fragment" section (because this is where you find the information on chromosome)
"start", "end", "strand", "sequence" in the "gap5" section (because this is where you will get the sequence and other related information for the region in 5-prime of the genes)
After, choose the condition to which you want to limit your search:
Choose "product" of the "cds " section, choose "REGEXP" and write "[[:<:]]Mg[[:>:]]|Magnesium".
Choose "size" of the "gap5 " section, choose ">=" and write "25".