Thanks for your purchase and sorry for late response.
1) I just could not find a way to setup the software for the amount to invest in each entry;
Stockalyze, as of now, always invests the entire amount and so no configuration is present to change this.
2) How do I see the backtest ploted in a graph? We i add indicator to the graph, it shows a lot of entry and sell that does not appear in the backtest result.
You can add signal marker (hit Ctrl+4 in chart window) to show buy/sell signals on chart. But yes, in backtesting the entry/exit happen at the first signal only and so subsequent same signals are ignored. For example you can get another buy signal after a buy signal without a sell signal in between. In that case backtesting does nothing on second buy signal as it had invested entire amount in first buy signal itself.
3) Can I set the backtest data with inicial and final date (like in scan stock) other than by number of records?
Actually earlier it used to be exactly this but when intraday support was added this was changed to number of records. Is it too inconvenient with number of records? Please let me know so that I can decide about making this change.
4) Is it possible to add the trading cost to backtest?
As of now it is not there but I have a plan for that.
I hope I have answered your queries. Please let me know if you have any more queries.