born,
May I suggest that you write a letter to the bigwigs?
Explain how you really liked the previous job because of the opportunity it provided for growth relative to your performance.
Tell them that you like the company, but feel this new position appears to stunt this growth and you feel your long term value will be diminsished.
Ask them to detail your options for further development and opportunities.
It may not change things immediately, but it will show a drive and work ethic that all employers expect but rarely receive.
In the meantime, it's OK to keep an eye out for other jobs, but embrace this new position and kick ass.
After a few months, if you're in a rut, ask for a review and an opportunity to discuss your long term plans.
You said you're molding? What type?
If it's in the plastics industry, shoot me an email
cape naz at comcast
dot net