Traveling through sheet and slow, very slow

I just downloaded 4.4.051. My program that was reading the Excel sheet has become VERY slow. What was done in 3 second is taking 60-30 seconds now. I am traveling on an excel sheet to find positions of specific text with .Range[x,y] command. It is slow... (also saving an excel sheet becomes very slow).
I have functions like : GoToTheNextFilledPosition, GoToTheNextEmptyPosition,... if I loop with Range[x,y] for more then 265 places (without finding what I want) then an error is thrown.
Also I keep positions like thisSpecialPosition = Range[x,y]. If I browse them after a while for changing the format of the sheet (other borders, colors, etc...) then the address becomes when debugging unusefull, meaning it is not nulll, it is marked with a red exclam.-icon when debugging in VS2005.

Hi Werner Plumot ,

We are extremely Sorry for the inconvenience. I need 2 more days to discuss this issue with my team an get back to you.

Thanks for using Syncfusion XlsIO.

With regards,
Chella.

Hi Werner Plumot ,

I seriously regret for the delay. Can you please create a Direct-Trac incident for this issue so that I can give you some samples to test the performance between various operations?

We are extremely sorry for the inconvenience.
Thanks for your interest in Syncfusion Essentials XlsIO.

With regards,
Chella.

I placed it on the Direct Trac but It seems that it is slow in debug mode.

Hi Werner,

The performance issue is something we are working on currently. However, since there are major changes being made to the code it can also take a little bit more time to get a stable version out, but its something we are looking into very seriously. We regret for the inconvenience caused. Please let me know if you have any concerns regarding this issue.

Thanks,
Melba