Answered Condition in getImageList -- how to compose it?

try

&where=`{"num:<":"10"}`

this is a json-style array (key/value - pairs)
http://www.json.org/

the key is delimted by ':'
first part - the fieldname
second part - the operator

possible operators, see:
https://github.com/Bruno17/MIGX/blob/master/core/components/migx/model/migx/migx.class.php#L1966

the value is the value, you are searching for.

the syntax is nearly the same as in getResources or many other snippets where-property

&where=`{"num:lt":"10"}`

this should work:

&where=`{"num:>=":"10","num:<":"20"}`

Is there any way this works with having multiple categories on each items?

Example i have categories "Category 1, Category 2, Category 3, Category 4, Category 5"

Now on my MIGX items, i can tag each item with categories above (i.e. Category 1, Catgory 2) using multilist tv with output separator with comma (,).

So let say on item 1, i have selected 3 categories on tv named [tags] so the value would be

[tags] => Category 1, Category 2, Category 3

Let say i would like to filter my MIGX items with tags, on my URL it will be

http://www.site.com/gallery/?tags=Category+1

and my MIGX snippet is

[[getImageList? &tvname=`gallery` &tpl=`gallery-tpl` &where=`[[!FilterTags]]`]]

Here's my FilterTags snippet;

$output = '';

if(isset($_GET['tags'])) {
	$tag = $_GET['tags'];
	$output = '{"tags:LIKE":"%'.$tag.'%"}';
}

return $output;

but this doesn't seem to work. Any idea why? or what did i miss? Thanks