How do I sort a text field from right to left?

Make sure the field is numeric. If it is a text field, that's how it will be sorted.

I understand your questions and will post a response if I can before my plane leaves.

you will need to create field for sorting purposes that looks like this

14054.000 
14054.001,
14054.020
14054.100

If you are pretty confident that the field will only contain numbers, then you can change its data type to numeric.

It will only contain numbers. 
I have tried it that way but when I increase the decimal the 14054.1 becomes 14054.10 and I already have a 14054.10 document

Numerically speaking, 14054.1 is the same as 14054.10 or 14054.100. The trailing zeroes does not change the value. Now, if you already have the value, and you sort them based on that number, they will appear together. I have another question: What do you mean "14054.10 document?" Can you provide more context?

Not tested buy try this as a sort field. You do not need to display it on the report, just sort on it.  This is a formula text field type

var text LeftOfDecimal = Left([my field],".");

var text RightOfDecimal = IF(Contains([my field],"."), Right([my field],".");

var text NewRightOfDecimal = Right("000" &  $RightOfDecimal,3);

If(Trim([my field]<>"", List(".", $LeftOfDecimal, $NewRightOfDecimal)

If there are any syntax error or problem, please post your code and the error message as this was not tested.