Modification of an existing MT4 EA

I have an MQL4 EA that works on 2 charts at the same time.  On the settings section the EA asks for a variable called ‘Maximum delay’.  And based on the number I give there, it creates a random number between 1 and that number.  Ex: If the Maximum delay is 10,000, it creates a random number between 1 and 10,000. Ex: 4516

It then puts that number on the chart and starts counting down from that number. As soon as the count down goes to zero, it opens the trades.

You can see the count down functionality on the video here:
https://gyazo.com/a23597b242fcfd3de09d802d43cb5fbb

Change 1:

The problem is that the countdown continues even on Saturdays and Sundays but it cannot open a trade as the market is closed. So, the countdown continues and goes to zero during the weekend.  As soon as the market opens it opens the trade as the count down is already waiting at zero.

It should actually stop where it is when the MT4 date/time turns to Saturday (or maybe when it stops receiving ticks?).  So, if the counter shows 2555 when the date turns to Saturday I want the counter to stop there and continue from 2555 when the market re-opens. So, the new trade is opened only after the counter goes to zero during market hours.

The settings of the EA has a section for trading days below and it actually works in terms of opening trades but it doesn’t stop the counter when the date is outside of trading dates.

http://prntscr.com/1z08f4t

Ex: Today is Tuesday. If I set Tuesday trading as 'false' on the EA it continues to count down. It shouldn't. 

Can a solution be created for this?

Change 2:

The counter start is determined based on this number on the settings section:
http://prntscr.com/1z09gk3

It basically picks a random value between 1 and that number on settings section and counts down for that many seconds before it opens a new trade.  Ex: if the random value is 3000, it counts down 3000 seconds before it opens a trade. 

There are 2 problems here. One of them is that the random value is never exceeding 30,000.  I made a research on that and fond that the EA the programmer used mathrand() function and it seems to support a number only up to 32767. So, I need a fix there. When I put a number like 650000 I need it to find me a random number up to 650000.  Ex: 375969. Currently it only finds me a number smaller than 32767.

The other problem is:

On top of the Maximum delay field I would like to add another field: Minimum delay(seconds): [TEXTBOX]

And  I would like the random value to be calculated from minimum delay to maximum delay instead of between 1 to the maximum delay.
Ex: Minimum delay(seconds) = 1000
      Maximum delay(seconds)= 8000

In this case it should create the random number from 1000 to 8000 instead of 1 to 8000.

When the random value is created I would like the trades opened when the count down from that number goes down to zero. (it already does this at the moment and I would like this functionality to be protected so it continues working the same way)