can't access tricolor bootloader screen

Hello -

In order to flash a new rom for the first time, I have just  installed Hard-SPL-Diamond-OliNex.zip . Everything seems to be working fine (original settings etc as opposed to my own settings - ringtones, colors etc) 

BUT, Now I cannot access the bootloader screen to confirm installation (i.e. which hard SPL is there. maybe it's still the original and the installation didn't happen)
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* Tried running the (xda devellopers) enterbootloader app that comes with the .zip download.  (from internal storage>programs and also from the standard program folder, in the device)
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In both cases i get a blank screen with a white line in the middle somewhere that fades away pretty quickly.

* so I tried hard resetting but found it physically impossible to press volume key, ok button and get the stylus to the reset button all at once!

Thanks in advance,

alex    

HI -
just to clarify:
 for the bootloader screen - with the diamond switched on (power) you hold the volume down and hit the reset button with the stylus.  OK.

This is what i did before installing the new hard spl, and I got the three colour screen with the SPL information  on it. 

However now the keystrokes get me a blank screen.

That is my difficulty right now.  Any clues as to reason or solution?  Have tried to manually enter bootloader with xda's facility, but this too failed.

thanks.

Alex