Is there a way for me to create or have a sub-account for Helm with limited permissions for some users? I want to delegate some of the site administration but would like to have control over the main Helm account.

Do you own reseller plan?

Nope.

Oh, there's a follow-up question...

Do you have a utility, or do you know of a way for me to allow email account holders to change their password outside of Helm? I saw a hack for Uebmiau, but it only seems to works with C Panel, not Helm. I tried and succeeded in installing my own UM (to customize the scheme), but the password hack I tried returns an error. Also, is there another mail reader that I could use aside from UM?

I'm hoping to find a solution so that all my future projects would adopt the same fix. So far, I don't see myself using a reseller plan for the meantime.

Thanks for your time.

No there is no way to do it outside Helm.
BTW we can host your mail on the linux box and just change MX records to point to linux mailservers thus you'll be able to use linux based webmails like Horde, Neomail, etc.

Thanks for the info, Serge.

Would that option (host the email in a Linux box) entail additional charges? If not, then I'd like that. And should I move to the Linux mail server, do I open a support ticket also?

Again, thanks in advance.

I'm using this period as a learning thing about your services so I know what to do when I start moving my other projects here.

You should open a ticket concerning this.
We'll activate this service for you.