I think that your condition is wrong:
the first "IF" sequence choose between >=4,5 and <4,5, all other values are excluded because the condition <4,5 is yet satisfied.
To set intervals you have to (for instance):
If(Cond >=4,5, Red
if (Cond<4,5 AND Cond >=3, Green,
if((Cond >=1 AND Cond <3, Blue, White
Hope it helps.