I answer some common questions:

Is it real time updates or can it only be used to download the data after market has closed?

In real time with the data provided by yahoo, clearly if yahoo provides some symbols delayed they will be too.

How many symbols does it support?

Anything you want, clearly the increase in symbols increases the delay in part

If I remove the symbols from the options, what happens?

Nothing happens, the options are used only when creating custom symbols, once created the service will identify them and keep them updated.

Can I perform backtests on these symbols?

Of course, you just have to check that in the symbol properties the settings are correct for what you want to do.

If you have any other questions, feel free to ask them below, I will be happy to answer them.

Also any new functions that you want to suggest me, if possible I will try to implement them in the next versions.

The platform does not prevent you, but I do not recommend it, the service already tries to do its job as quickly as possible trying to make the most of the maximum number of requests to the yahoo finance servers. By activating multiple services from the same IP, you only risk not receiving replies from their servers for an indefinite period of time, so NO do not start multiple services from the same IP.

Yahoo has changed and for now disabled the access to real time data, I'm working to find a solution, I'm very sorry but this problem was not caused by me. As it stands this is yahoo's answer https://bit.ly/yahoo-finance-api-feedback