Conditional is not working, tired the example!

I am I am trying to use this plug-in but when I use a drop-down menu, the if then part doesn’t work, except if the first choice of the menu is the one that activates the contitional.

<fieldset>
<legend>try</legend>
</fieldset>

Which fields would you like to view? [select pick-fields “Basic fields” “Advanced fields” “All fields”]

[group basic]
<fieldset>
<legend>Basic Fields</legend>

Your name
[text your-name]
</fieldset>
[/group]

[group advanced-fields]
<fieldset>
<legend>Advanced Fields</legend>
Your operating system
[select pick-os “Windows” “Mac” “Linux” “Android” “iOS” “Other”]
[group other][text other_os][/group]

Some advanced fields
[text adv]
</fieldset>

[/group]

Thanks for the support!

The page I need help with: [log in to see the link]