Yes, you can use Portfolio Optimiser to optimise for amount. Alternatively, you can also set the current quantity (number of shares) of each symbol to be equal to the investment amount and then perform the optimization process. The following three videos explain the different ways of optimizing.
Optimize for Current Quantities:
Optimize for Cash:
Optimize for Equal Allocation:
Useful Links:
Portfolio Optimiser India
How to Use Portfolio Optimiser (YouTube)