processing a string by Excel

Hi,
I get equation in the form of a string from the output of a software that I want to modify by Excel. I am no expert in Excel and I am wondering if some expert in Excel at this forum can do this for me.
Pls see the attached Excel file. The string in cell A1 is an example string that I will be explaining how I want this string to be modified. Here are the attributes of the string.

a. The string will have ASCII characters in it.

b. The string is a mathematical equation. I will be pasting it into Mathcad once the Excel program modifies it.

c. The string has parameters and mathematical operators in it (+,-,*,/,^). Each parameter is seperated from another parameter by at least one space. There is no space in a parameter. So, each parameter starts with a space and ends with a space. The parameters of the example string in cell A1 are listed from cells A5 to A14 in the attached file.

d. If a parameter has paranthesis in it (), then the program will disregard any character in the parameter outside the paranthesis and take the characters inside the paranthesis. For example, it will modify the parameter in cell A5 from "F(u)_X1" to "u". If the parameter has no paranthesis in it, like the one in cell A14, then it will take it as is.

e. The format of the string is such that the multiplication sign may be omitted between parameters. If there is no mathematical operator between two adjacent parameters, it should be assumed that the math operator between them is multiplication. So, the Excel program should insert a multiplication sign between them.

f. Then the program will reassemple the string in the form of an equation by appropriately keeping the mathematical operators in the original expression.

The cells B5 to B14 show the modified parameters of the original parameters in the string in cell A1. The Excel program should put together the parameters in B5 to B14 as shown in cell A18.

I will appreciate if someone can write an Excel program for me that accomplishes this. Many thanks.

Mark Neil