There is always room for improvement. But I think the current website is ok.
I already remarked on the currency issue.
I would change the ‘screenshots’ page into a ‘tour’ page with some text. And space the screenshots out.
I wouldn’t bother to put your email and social media at the top. That is prime real estate. Why should that be the first thing they see? Move it to the bottom. Email probably should be clickable.
Copy is a bit flabby in places. Don’t use 10 words if 5 would suffice. Less is more.
“The Ultimate Stock Portfolio Management Software” is a bit bland IMHO. Maybe choose a strap line that emphasizes how yours is better than others.
Maybe mention the privacy benefits of storing it on your own computer, rather than the cloud.
HTH. It is much easier to criticize someone else’s website than improve your own. ;0)